597 research outputs found

    Changes in oxidant-antioxidant status in young diabetic patients from clinical onset onwards

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    Oxidative stress has been implicated as a mechanism underlying hyperglycaemia-associated cellular damage and could play a role in the development of diabetes-related complications. This study aimed to evaluate the significance of changes in oxidant-antioxidant status in 176 child and adolescent diabetic patients at clinical onset, during disease progression and when early microvascular complications appeared. Indicative lipid and protein oxidation markers and antioxidant defence activity were measured in plasma and correlated with clinical data, diabetes duration, long-term glycometabolic control and serum lipids. Compared with their respective age-matched controls, diabetic patients had greater oxidative damage to lipids and proteins, demonstrated through the analysis of hydroperoxides, lipoperoxides and oxidation protein products, all of which were significantly raised at onset, decreased during the first 1.5 years of evolution and rose progressively thereafter. Plasma levels of oxidizable lipids were significantly associated with lipid and protein oxidation products. Overall, plasma antioxidant capacity was significantly and consistently lower from clinical onset onwards. These results suggest that insulin therapy in the first year improved metabolic and oxidant homeostasis and consequently hyperglycaemia-derived biomolecular oxidative damage. Diabetes-associated hyperlipidaemia is related to lipid and protein oxidation processes, which supports the concept of glucose toxicity and lipotoxicity being interrelated. The greatest increase in lipid and protein oxidative damage biomarkers in young diabetic patients with premature microangiopathy points to oxidative stress as a possible contributing mechanism of microvascular dysfunction. Consequently, tight lipid and glycometabolic control may have therapeutic potential by diminishing oxidative tissue-damaging effects of hyperglycaemia

    Rationale and design of the dual-energy computed tomography for ischemia determination compared to “gold standard” non-invasive and invasive techniques (DECIDE-Gold) : a multicenter international efficacy diagnostic study of rest-stress dual-energy computed tomography angiography with perfusion

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    Background: Dual-energy CT (DECT) has potential to improve myocardial perfusion for physiologic assessment of coronary artery disease (CAD). Diagnostic performance of rest-stress DECT perfusion (DECTP) is unknown. Objective: DECIDE-Gold is a prospective multicenter study to evaluate the accuracy of DECT to detect hemodynamic (HD) significant CAD, as compared to fractional flow reserve (FFR) as a reference standard. Methods: Eligible participants are subjects with symptoms of CAD referred for invasive coronary angiography (ICA). Participants will undergo DECTP, which will be performed by pharmacological stress, and participants will subsequently proceed to ICA and FFR. HD-significant CAD will be defined as FFR\ua0 64\ua00.80. In those undergoing myocardial stress imaging (MPI) by positron emission tomography (PET), single photon emission computed tomography (SPECT) or cardiac magnetic resonance (CMR) imaging, ischemia will be graded by % ischemic myocardium. Blinded core laboratory interpretation will be performed for CCTA, DECTP, MPI, ICA, and FFR. Results: Primary endpoint is accuracy of DECTP to detect 651 HD-significant stenosis at the subject level when compared to FFR. Secondary and tertiary endpoints are accuracies of combinations of DECTP at the subject and vessel levels compared to FFR and MPI. Conclusion: DECIDE-Gold will determine the performance of DECTP for diagnosing ischemia

    Autonomous on-board data processing and instrument calibration software for the SO/PHI

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    The extension of on-board data processing capabilities is an attractive option to reduce telemetry for scientific instruments on deep space missions. The challenges that this presents, however, require a comprehensive software system, which operates on the limited resources a data processing unit in space allows. We implemented such a system for the Polarimetric and Helioseismic Imager (PHI) on-board the Solar Orbiter (SO) spacecraft. It ensures autonomous operation to handle long command-response times, easy changing of the processes after new lessons have been learned and meticulous book-keeping of all operations to ensure scientific accuracy. This contribution presents the requirements and main aspects of the software implementation, followed by an example of a task implemented in the software frame, and results from running it on SO/PHI. The presented example shows that the different parts of the software framework work well together, and that the system processes data as we expect. The flexibility of the framework makes it possible to use it as a baseline for future applications with similar needs and limitations as SO/PHI.Comment: Conference: SPIE Astronomical Telescopes + Instrumentatio, Software and Cyberinfrastructure for Astronomy

    A protein with simultaneous capsid scaffolding and dsRNA-binding activities enhances the birnavirus capsid mechanical stability

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    Viral capsids are metastable structures that perform many essential processes; they also act as robust cages during the extracellular phase. Viruses can use multifunctional proteins to optimize resources (e.g., VP3 in avian infectious bursal disease virus, IBDV). The IBDV genome is organized as ribonucleoproteins (RNP) of dsRNA with VP3, which also acts as a scaffold during capsid assembly. We characterized mechanical properties of IBDV populations with different RNP content (ranging from none to four RNP). The IBDV population with the greatest RNP number (and best fitness) showed greatest capsid rigidity. When bound to dsRNA, VP3 reinforces virus stiffness. These contacts involve interactions with capsid structural subunits that differ from the initial interactions during capsid assembly. Our results suggest that RNP dimers are the basic stabilization units of the virion, provide better understanding of multifunctional proteins, and highlight the duality of RNP as capsidstabilizing and genetic information platformsThis work was supported by grants from the Spanish Ministry of Economy and Competitivity (FIS2011-29493 to PJP, BFU2011-29038 to JLC and BFU2014-55475R to JRC) and Comunidad Autónoma de Madrid (S2013/MIT-2850 to JLC and S2013/MIT-2807 to JRC

    Pengembangan Media Pembelajaran Fisika Berbasis Multimedia Interaktif Terintegrasi Dengan Lks Pokok Bahasan Hukum Newton Tentang Gerak Kelas X Sma/ma

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    Penelitian ini bertujuan untuk: (1) mengembangkan media pembelajaran fisika berbasis multimedia interaktif dengan menggunakan software adobe flash dan XML pada pokok bahasan Hukum Newton tentang gerak; (2) mengetahui kelayakan media pembelajaran fisika berbasis multimedia interaktif menggunakan software adobe flash dan XML pada pokok bahasan Hukum Newton tentang gerak yang dikembangkan; (3) mengetahui pencapaian hasil belajar siswa setelah mengikuti proses pembelajaran menggunakan media pembelajaran fisika berbasis multimedia interaktif terintegrasi dengan lembar kerja siswa hasil pengembangan. Penelitian ini merupakan penelitian dan pengembangan (R&D) yang mengacu pada model yang dikemukakan oleh Sugiyono. Kelayakan media divalidasi oleh ahli materi, ahli media dan praktisi. Subjek Ujicoba penelitian ini adalah siswa kelas X SMA N 3 Sukoharjo tahun akademik 2013/2014 sebanyak 43 siswa dengan rincian 10 siswa sebagai subjek ujicoba produk dan 33 siswa sebagai subjek ujicoba pemakaian. Berdasarkan hasil analisis data disimpulkan: (1) media pembelajaran fisika berbasis multimedia interaktif terintegrasi dengan lembar kerja siswa berhasil dikembangkan dengan menggunakan Software Adobe Flash dan XML dengan hasil produk dikemas dalam keping CD yang didalamnya berisi software utama media dan beberapa file pendukung dari media tersebut. Media disajikan dengan dua pembagian materi yaitu materi pembelajaran dan materi penjelasan yang diproteksi serta berisi bank soal yang dapat diupdate. Media pembelajaran dikembangkan dengan mengacu pada langkah yang diberikan oleh Sugiyono dan telah tervalidasi; (2) media pembelajaran fisika berbasis multimedia interaktif terintegrasi dengan lembar kerja siswa yang dikembangkan layak digunakan dengan kategori baik; (3) pencapaian hasil belajar peserta didik setelah mengikuti proses pembelajaran menggunakan media pembelajaran fisika berbasis multimedia interaktif terintegrasi dengan lembar kerja siswa mengalami peningkatan pada aspek pengetahuan
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