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93.
Complement activation and atherosclerosis 总被引:19,自引:0,他引:19
Atherosclerosis is an inflammatory disease mediated through the action of monocyte/macrophages, complement and T-lymphocytes. C5a and monocyte chemotactic factor released during complement activation in the arterial wall may participate in the initial monocyte recruitment. Assembly of C5b-9 on cells of the arterial wall may also induce cell lysis. On the other hand, sublytic assembly of C5b-9 on smooth muscle cells (SMC) and endothelial cells (EC) induces cell activation and proliferation. Analysis of mitogen activated protein kinases (MAPK) pathways induced by C5b-9 in aortic SMC revealed that extracellular signal regulated kinase (ERK) 1, c-jun NH2-terminal kinase (JNK) 1, and p38 MAPK are all activated by C5b-9. ERK1 activity was inhibited by wortmannin suggesting that ERK1 pathway is activated through phosphatidyl inositol -3 (PI 3-) kinase. Sublytic C5b-9 assembly on the plasma membrane was also able to activate Janus kinase (JAK) 1, signal transducer and activator (STAT) 3 and STAT4 in EC. JAK1 but not STAT3 activation induced by C5b-9 is dependent on Gi protein activation. New evidence accumulated during the last decade support the role of complement activation in both initiation and progression of the atherosclerotic lesions. Complement system activation is a major component of the chronic inflammatory process associated with atherosclerosis. 相似文献
94.
Erlend Stav Ståle Walderhaug Marius Mikalsen Sten Hanke Ivan Benc 《International journal of medical informatics》2013,82(11):e269-e293
IntroThe proper use of ICT services can support seniors in living independently longer. While such services are starting to emerge, current proprietary solutions are often expensive, covering only isolated parts of seniors’ needs, and lack support for sharing information between services and between users. For developers, the challenge is that it is complex and time consuming to develop high quality, interoperable services, and new techniques are needed to simplify the development and reduce the development costs.This paper provides the complete view of the experiences gained in the MPOWER project with respect to using model-driven development (MDD) techniques for Service Oriented Architecture (SOA) system development in the Ambient Assisted Living (AAL) domain.MethodTo address this challenge, the approach of the European research project MPOWER (2006–2009) was to investigate and record the user needs, define a set of reusable software services based on these needs, and then implement pilot systems using these services. Further, a model-driven toolchain covering key development phases was developed to support software developers through this process. Evaluations were conducted both on the technical artefacts (methodology and tools), and on end user experience from using the pilot systems in trial sites.ResultsThe outcome of the work on the user needs is a knowledge base recorded as a Unified Modeling Language (UML) model. This comprehensive model describes actors, use cases, and features derived from these. The model further includes the design of a set of software services, including full trace information back to the features and use cases motivating their design. Based on the model, the services were implemented for use in Service Oriented Architecture (SOA) systems, and are publicly available as open source software. The services were successfully used in the realization of two pilot applications. There is therefore a direct and traceable link from the user needs of the elderly, through the service design knowledge base, to the service and pilot implementations.The evaluation of the SOA approach on the developers in the project revealed that SOA is useful with respect to job performance and quality. Furthermore, they think SOA is easy to use and support development of AAL applications. An important finding is that the developers clearly report that they intend to use SOA in the future, but not for all type of projects. With respect to using model-driven development in web services design and implementation, the developers reported that it was useful. However, it is important that the code generated from the models is correct if the full potential of MDD should be achieved.The pilots and their evaluation in the trial sites showed that the services of the platform are sufficient to create suitable systems for end users in the domain.ConclusionsA SOA platform with a set of reusable domain services is a suitable foundation for more rapid development and tailoring of assisted living systems covering reoccurring needs among elderly users. It is feasible to realize a tool-chain for model-driven development of SOA applications in the AAL domain, and such a tool-chain can be accepted and found useful by software developers. 相似文献
95.
Florin Stanciu Simona Vladu Veronica Cu??r Daniela Cocioab? Florentina Iancu Adnana Cotolea Ionel Marius Stoian 《Croatian medical journal》2013,54(3):232-237
Aim
To establish allele frequencies and genetic parameters for 5 new European Standard Set short tandem repeat (STR) loci in the population of Romania and to compare them with those in other populations.Methods
DNA was isolated using QIAamp 96 DNA Swab BioRobot Kit and Chelex 100 methods. Polymerase chain reaction amplification was done using Investigator ESSplexPlus Kit (D1S1656, D2S441, D2S1338, D3S1358, D8S1179, D10S1248, D12S391, D16S539, D18S51, D19S433, D21S11, D22S1045, FGA, TH01, and vWA). For DNA typing, Applied Biosystems 3500/3500xL Genetic Analyzer was used. Statistical analysis was done using Powerstats, GDA, and Arlequin software.Results
Power of discrimination and polymorphism information content was highest for two new ESS loci, D1S1656 and D12S391. Comparison of allele frequencies for 5 new ESS loci in Romanian population with previously published population data showed significant differences for all compared populations, with the exception of Hungary. Geographically more distant populations, such as Spain, Sweden, United Kingdom, Germany, and Portugal differed more than closer populations.Conclusion
New ESS STR loci are very useful for the analysis of forensic samples (persons or traces) due to their characteristics (shortness and high polymorphism). In comparisons with other common STR markers, they have a higher power of discrimination and also higher polymorphism information content, and could be used in any national DNA database.The establishment of standard sets (or common sets) of short tandem repeat (STR) markers which had first been a necessity for the forensic scientific community, as a result of globalization became a necessity for the worldwide law enforcement agencies. STR markers standard sets facilitate communication and judicial transmission of the forensic DNA typing results between different forensic groups or countries (1).Although several STR sets have been proposed (2), three of them are most frequently used: Interpol Standard Set of Loci – ISS (FGA, TH01, VWA, D3S1358, D8S1179, D18S51, D21S11), US Core Loci – CODIS (CSF1PO, FGA, TH01, TPOX, VWA, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11), and European Standard Set of Loci – ESS (D3S1358, VWA, D8S1179, D21S11, D18S51, TH01, FGA, D1S1656, D2S441, D10S1248, D12S391, D22S1045).The five new European Standard Set STR loci studied in Romanian population are an upgrade of an earlier version of ESS consisiting of 7 STRs (3), adopted by the European Council in 2001. The DNA Working Group of the European Network of Forensic Science Institutes (ENFSI) reviewed the usefulness of the ESS in light of the increased exchange of DNA analysis results in 2009 and recommended the expansion with 5 new ones (4).Romania adopted the new 5 ESS loci and started to use them at the national level at the beginning of 2012 as part of the Investigator ESSplex Plus Kit, which replaced the AmpFlSTR Identifiler PCR Amplification Kit used before for Romanian National DNA Database supplying. As a consequence, and due to the lack of any study involving D10S1248, D22S1045, D2S441, D1S1656, and D12S391 loci in the Romanian population, allele distribution and genetic parameters of these loci have to be determined. The aim of this study was to establish allele frequencies and genetic parameters for 5 new ESS loci in population of Romania and to compare them with those in other populations . 相似文献96.
Eschmann SM Bitzer M Paulsen F Friedel G Besenfelder H Horger M Reimold M Dittmann H Pfannenberg AC Bares R 《Nuclear medicine communications》2004,25(9):909-915
AIM: To evaluate functional-anatomical imaging with 2-[F]fluoro-2-deoxy-D-glucose (F-FDG) utilizing a dual-head coincidence gamma camera with an integrated X-ray transmission system for attenuation correction, anatomical mapping, and image fusion compared to conventional diagnostics by computed tomography (CT) in non-small cell lung cancer (NSCLC). METHODS: Thirty-five patients with NSCLC underwent FDG imaging of the thoracic area using a dual-head coincidence gamma camera (DHC) with an integrated X-ray transmission system. State-of-the-art CT scans had been performed before. Whole-body dedicated FDG positron emission tomography (PET) was performed immediately prior to DHC. Staging by CT and DHC, and DHC with integrated image fusion (FDHC) were re-evaluated with regard to detectable lesions, correct anatomical diagnoses, and clinical impact. Results of DHC and PET were compared for analysis of limitations of DHC. RESULTS: One hundred and thirteen tumour lesions were identified by CT. DHC detected 128 lesions overall: 102 true positive CT lesions were confirmed, 25 additional lesions were detected which affected staging in eight patients, and one false positive lung lesion did not show up in DHC. Nine CT lesions were missed by DHC (lymph node and lung). PET detected 150 areas of focally enhanced uptake, delivering two false positive results (nuchal muscles, pneumonia). Final evaluation confirmed 148 malignant lesions. Compared to CT, the results of DHC changed staging or treatment in 8/35 patients (23%). Lesion detection by DHC was limited by tumour size and intensity of FDG uptake. Image fusion provided relevant clinical information in 9/35 patients (26%). CONCLUSION: Functional imaging in NSCLC with this dual-head gamma camera is superior to morphological imaging by CT, although inferior to dedicated PET imaging. Combined functional-anatomical imaging has the potential to improve staging and localization procedures before surgery or radiotherapy. 相似文献
97.
Walid Elmahdy Mohamed Osman Mohamed Farag Ahmad Shoaib Haisam Saad Keith Sullivan Unni Krishnan Samer Nashef Marius Berman 《Seminars in thoracic and cardiovascular surgery》2021,33(1):23-30
PPM was highly associated with long-term all-cause mortality. Small Aortic Valve Annulus MDT (SAVA-MDT) exploring options to prevent PPM, including the implantation of newer generation prosthetic valves, aortic root enlargement and TAVI, should be established. 相似文献
98.
V Andrew Stenger Marius S Giurgi Fernando E Boada Douglas C Noll 《Magnetic resonance in medicine》2006,56(3):692-697
An extension of the "UNaliasing by Fourier encoding the Overlaps using the temporaL Dimension" (UNFOLD) method to the excitation domain (XUNFOLD) is presented to improve the temporal resolution of multishot tailored RF (TRF) pulses. Multishot three-dimensional TRF pulses were designed to produce a time series of images with periodically aliased excitation profiles. The XUNFOLD method is shown to remove the excitation profile aliasing from the dynamic imaging data by filtering in the temporal frequency dimension. The technique is demonstrated to improve the temporal resolution of simulated functional MRI (fMRI) activation in a time series of brain images. 相似文献
99.
Marius E. Mayerhoefer MD PhD Wolfgang Schima MD MSc Siegfried Trattnig MD Katja Pinker MD Vanessa Berger‐Kulemann MD Ahmed Ba‐Ssalamah MD 《Journal of magnetic resonance imaging : JMRI》2010,32(2):352-359
Purpose:
To determine the feasibility of texture analysis for the classification of liver cysts and hemangiomas, on nonenhanced, zero‐fill interpolated T1‐ and T2‐weighted MR images.Materials and Methods:
Forty‐five patients (26 women and 19 men; mean age, 58.1 ± 16.9 years) with liver cysts or hemangiomas were enrolled in the study. After exclusion of images with artifacts, T1‐weighted images of 42 patients, and T2‐weighted images of 39 patients, obtained at 3.0 Tesla (T), were available for further analysis. Texture features derived from the gray‐level histogram, co‐occurrence and run‐length matrix, gradient, autoregressive model, and wavelet transform were calculated. Fisher, probability of classification error and average correlation (POE+ACC), and mutual information coefficients were used to extract subsets of optimized texture features. Linear discriminant analysis (LDA) in combination with k nearest neighbor (k‐NN) classification, and k‐means clustering, were used for lesion classification.Results:
LDA/k‐NN produced misclassification rates of 16–18% on T1‐weighted, and 12–18% on T2‐weighted images. K‐means clustering yielded misclassification rates of 15–23% on T1‐weighted, and 15–25% on T2‐weighted images.Conclusion:
Texture‐based classification of liver cysts and hemangiomas is feasible on zero‐fill interpolated MR images obtained at 3.0T. Further studies are warranted to investigate the value of texture‐based classification of other liver lesions, such as hepatocellular and cholangiocellular carcinoma, on MRI. J. Magn. Reson. Imaging 2010;32:352–359. © 2010 Wiley‐Liss, Inc. 相似文献100.