19 research outputs found

    Three-dimensional easy morphological (3-DEMO) classification of scoliosis, part I

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    BACKGROUND: While scoliosis has, for a long time, been defined as a three-dimensional (3D) deformity, morphological classifications are confined to the two dimensions of radiographic assessments. The actually existing 3-D classification proposals have been developed in research laboratories and appear difficult to be understood by clinicians. AIM OF THE STUDY: The aim of this study was to use the results of a 3D evaluation to obtain a simple and clinically oriented morphological classification (3-DEMO) that might make it possible to distinguish among different populations of scoliotic patients. METHOD: We used a large database of evaluations obtained through an optoelectronic system (AUSCAN) that gives a 3D reconstruction of the spine. The horizontal view was used, with a spinal reference system (Top View). An expert clinician evaluated the morphological reconstruction of 149 pathological spines in order to find parameters that could be used for classificatory ends. These were verified in a mathematical way and through computer simulations: some parameters had to be excluded. Pathological data were compared with those of 20 normal volunteers. RESULTS: We found three classificatory parameters, which are fully described and discussed in this paper: Direction, the angle between spinal pathological and normal AP axis; Shift, the co-ordinates of the barycentre of the Top View ; Phase, the parameter describing the spatial evolution of the curve. Using these parameters it was possible to distinguish normal and pathological spines, to classify our population and to differentiate scoliotic patients with identical AP classification but different 3D behaviors. CONCLUSION: The 3-DEMO classification offers a new and simple way of viewing the spine through an auxiliary plane using a spinal reference system. Further studies are currently under way to compare this new system with the existing 3-D classifications, to obtain it using everyday clinical and x-rays data, and to develop a triage for clinical use

    Spatial resource wars: A two region example

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    We develop a spatial resource model in continuous time in which two agents strategically exploit a mobile resource in a two-location setup. In order to contrast the overexploitation of the resource (the tragedy of commons) that occurs when the player are free to choose where to fish/hunt/extract/harvest, the regulator can establish a series of spatially structured policies. We compare the three situations in which the regulator: (a) leaves the player free to choose where to harvest; (b) establishes a natural reserve where nobody is allowed to harvest; (c) assigns to each player a specific exclusive location to hunt. We show that when preference parameters dictate a low harvesting intensity, the policies cannot mitigate the overexploitation and in addition they worsen the utilities of the players. Conversely, in a context of harsher harvesting intensity, the intervention can help to safeguard the resource, preventing the extinction and also improving the welfare of both players

    Analysis of ferritin genes in Parkinson disease.

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    BACKGROUND: Genes that regulate iron metabolism may be involved in increasing brain iron content in Parkinson disease (PD). The ferritin L-chain is one of these genes, but the rare insertional mutations that cause neuroferritinopathy with basal ganglia degeneration have not yet been identified in PD. METHODS: We used denaturing HPLC (DHPLC) to investigate 124 PD patients and 180 controls for variations in the coding and in the 5' untranslated regions of the H- and L-ferritin genes. RESULTS: In the H-ferritin gene, we found one new and rather common intronic polymorphism and the K54R substitution in two controls. The L-ferritin gene showed a very common L55L polymorphism and four other types of DNA variations, three of which were in the patient cohort. A mutation of the conserved His133 to Pro was found in a PD patient and in his daughter. The patient did not show signs of neuroferritinopathy, but the mutation was associated with low L-ferritin levels and with mild chronic anemia. CONCLUSIONS: The results support the hypothesis that DNA variations in the ferritin genes are not a common cause for P

    Analysis of Uromodulin Polymerization Provides New Insights into the Mechanisms Regulating ZP Domain-mediated Protein Assembly

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    Uromodulin is the most abundant protein secreted in urine, in which it is found as a high-molecular-weight polymer. Polymerization occurs via its zona pellucida (ZP) domain, a conserved module shared by many extracellular eukaryotic proteins that are able to assemble into matrices. In this work, we identified two motifs in uromodulin, mapping in the linker region of the ZP domain and in between protein cleavage and glycosylphosphatidylinositol (GPI)-anchoring sites, which regulate its polymerization. Indeed, mutations in either module led to premature intracellular polymerization of a soluble uromodulin isoform, demonstrating the inhibitory role of these motifs for ZP domain-mediated protein assembly. Proteolytic cleavage separating the external motif from the mature monomer is necessary to release the inhibitory function and allow protein polymerization. Moreover, we report absent or abnormal assembly into filaments of GPI-anchored uromodulin mutated in either the internal or the external motif. This effect is due to altered processing on the plasma membrane, demonstrating that the presence of the two modules has not only an inhibitory function but also can positively regulate protein polymerization. Our data expand previous knowledge on the control of ZP domain function and suggest a common mechanism regulating polymerization of ZP domain proteins

    Protective effect of mitochondrial ferritin on cytosolic iron dysregulation induced by doxorubicin in HeLa cells

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    Doxorubicin (DOX) is an anticancer drug with cardiotoxic side effects mostly caused by iron homeostasis dysregulation. Mitochondria are involved in iron trafficking and mitochondrial ferritin (FtMt) was shown to provide protection against cellular iron imbalance. Therefore, we hypothesized that FtMt overexpression could limit DOX effects on iron homeostasis. Heart???s homogenates of DOXtreated C57BL/6 mice were analyzed for cytosolic and mitochondrial iron-related proteins??? expression and activity, revealing high cytosolic ferritin and ferritin-bound iron, low transferrin-receptor 1 and a strong hepcidin upregulation. Mitochondrial iron-related proteins (aconitase, succinatedehydrogenase, frataxin) seemed, however, unaffected, although a partial inactivation of superoxide dismutase 2 was detected. Importantly, the ectopic expression of FtMt in human HeLa cells partially reverted DOX-induced iron imbalance. Our results, while confirming DOX effects on iron homeostasis, demonstrate that DOX affects more cytosolic than mitochondrial iron metabolism both in murine hearts and human HeLa cells and that FtMt overexpression is able to prevent most of these effects in HeLa cell
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