1,033 research outputs found

    Hydrophilic interaction chromatography – mass spectrometry for metabolomics and proteomics:state-of-the-art and current trends

    Get PDF
    Among all the –omics approaches, proteomics and metabolomics have received increased attention over the last decade. Both approaches have reached a certain level of maturity, showing their relevance in numerous clinical applications, including biomarkers discovery, improved diagnosis, staging, and prognosis of diseases, as well as a better knowledge on various (patho-)physiological processes. Analytically, reversed-phase liquid chromatography – mass spectrometry (RPLC-MS) is considered the golden standard in proteomics and metabolomics, due to its ease of use and reproducilibity. However, RPLC-MS alone is not sufficient to resolve the complexity of the proteome, while very polar metabolites are typically poorly retained. In this context, hydrophilic interaction chromatography (HILIC) represents an attractive complementary approach, due to its orthogonal separation mechanism. This review presents an overview of the literature reporting the application of HILIC-MS in metabolomics and proteomics. For metabolomics the focus is on the analysis of bioactive lipids, amino acids, organic acids, and nucleotides/nucleosides, whereas for proteomics the analysis of complex samples and protein post-translational modifications therein using bottom-up, middle up/down proteomics and intact protein analysis is discussed. The review handles the technological aspects related to the use of HILIC-MS in both proteomics and metabolomics, paying attention to stationary phases, mobile phase conditions, injection volume and column temperature. Recent trends and developments in the application of HILIC-MS in proteomics and metabolomics are also presented and discussed, highlighting the advantages the technique can provide in addition or complementary to RPLC-MS, as well as the current limitations and possible solutions

    Nuclear Structure Calculations and Modern Nucleon-Nucleon Potentials

    Full text link
    We study ground-state properties of the doubly magic nuclei 4He, 16O, and 40Ca employing the Goldstone expansion and using as input four different high-quality nucleon-nucleon (NN) potentials. The short-range repulsion of these potentials is renormalized by constructing a smooth low-momentum potential V-low-k. This is used directly in a Hartree-Fock approach and corrections up to third order in the Goldstone expansion are evaluated. Comparison of the results shows that they are only slightly dependent on the choice of the NN potential.Comment: 5 pages, submitted to Physical Review

    Multi-scale analysis of lung computed tomography images

    Get PDF
    A computer-aided detection (CAD) system for the identification of lung internal nodules in low-dose multi-detector helical Computed Tomography (CT) images was developed in the framework of the MAGIC-5 project. The three modules of our lung CAD system, a segmentation algorithm for lung internal region identification, a multi-scale dot-enhancement filter for nodule candidate selection and a multi-scale neural technique for false positive finding reduction, are described. The results obtained on a dataset of low-dose and thin-slice CT scans are shown in terms of free response receiver operating characteristic (FROC) curves and discussed.Comment: 18 pages, 12 low-resolution figure

    Viscous-Inviscid Interactions in a Boundary-Layer Flow Induced by a Vortex Array

    Full text link
    In this paper we investigate the asymptotic validity of boundary layer theory. For a flow induced by a periodic row of point-vortices, we compare Prandtl's solution to Navier-Stokes solutions at different ReRe numbers. We show how Prandtl's solution develops a finite time separation singularity. On the other hand Navier-Stokes solution is characterized by the presence of two kinds of viscous-inviscid interactions between the boundary layer and the outer flow. These interactions can be detected by the analysis of the enstrophy and of the pressure gradient on the wall. Moreover we apply the complex singularity tracking method to Prandtl and Navier-Stokes solutions and analyze the previous interactions from a different perspective

    Automated detection of lung nodules in low-dose computed tomography

    Get PDF
    A computer-aided detection (CAD) system for the identification of pulmonary nodules in low-dose multi-detector computed-tomography (CT) images has been developed in the framework of the MAGIC-5 Italian project. One of the main goals of this project is to build a distributed database of lung CT scans in order to enable automated image analysis through a data and cpu GRID infrastructure. The basic modules of our lung-CAD system, consisting in a 3D dot-enhancement filter for nodule detection and a neural classifier for false-positive finding reduction, are described. The system was designed and tested for both internal and sub-pleural nodules. The database used in this study consists of 17 low-dose CT scans reconstructed with thin slice thickness (~300 slices/scan). The preliminary results are shown in terms of the FROC analysis reporting a good sensitivity (85% range) for both internal and sub-pleural nodules at an acceptable level of false positive findings (1-9 FP/scan); the sensitivity value remains very high (75% range) even at 1-6 FP/scanComment: 4 pages, 2 figures: Proceedings of the Computer Assisted Radiology and Surgery, 21th International Congress and Exhibition, Berlin, Volume 2, Supplement 1, June 2007, pp 357-35

    Mushroom-Based Supplements in Italy: Let’s Open Pandora’s Box

    Get PDF
    Mushrooms and derivates are well known to the scientific community for having different health benefits and exhibit a wide range of pharmacological activities, including lipid-lowering, antihypertensive, antidiabetic, antimicrobic, antiallergic, anti-inflammatory, anticancer, immunomodulating, neuroprotective and osteoprotective actions. In Europe, medical mushrooms are mainly marketed in the form of food supplements as single components or combined with other nutraceuticals. In this context, the first peculiarity that distinguishes it is the safety established through the “history of consumption” that characterizes that mushroom. However, the cultivation of medicinal mushrooms on a large scale is performed mainly in China, where most of the production facilities do not have internationally recognized good manufacturing practices, despite that many European companies that sell myotherapies are supplied by Chinese manufacturers. This is particularly evident in Italy, where an arsenal of mushroom products is marketed in the form of powders and extracts not always of ascertained origin and sometimes of doubtful taxonomic identification, and thus not meeting the quality criteria required. The growing interest in mycotherapy involves a strong commitment from the scientific community to propose supplements of safe origin and genetic purity as well as to promote clinical trials to evaluate its real effects on humans. The purpose of this research is to analyze different mushroom-based dietary supplements used in medicine as monotherapy on the Italian market and to evaluate their composition and quality. The molecular identification of the sequences with those deposited in GenBank allowed for identifying 6 out of 19 samples, matching with those deposited belonging to the species indicated in the label, i.e., Lentinula edodes (samples 1, 4, 12 and 18) and Ganoderma lucidum (samples 5 and 10). Samples containing Ganoderma, labeled in the commercial product as G. lucidum, showed sequences that showed homology of 100% and 99% with G. resinaceum and G. sichuanense. An additional investigation was carried out in order to determine the active fungal ingredients, such as ergosterol, aflatoxins, heavy metals, nicotine and total glucan. The results obtained and shown in the manuscript highlight how the data were not only in line with what is expected with respect to what is indicated in the labels
    • …
    corecore