Erythropoietin prevents neuronal apoptosis after cerebral ischemia and metabolic stress

Erythropoietin (EPO) promotes neuronal survival after hypoxia and other metabolic insults by largely unknown mechanisms. Apoptosis and necrosis have been proposed as mechanisms of cellular demise, and either could be the target of actions of EPO. This study evaluates whether antiapoptotic mechanisms can account for the neuroprotective actions of EPO. Systemic administration of EPO (5,000 units/kg of body weight, i.p.) after middle-cerebral artery occlusion in rats dramatically reduces the volume of infarction 24 h later, in concert with an almost complete reduction in the number of terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling of neurons within the ischemic penumbra. In both pure and mixed neuronal cultures, EPO (0.1–10 units/ml) also inhibits apoptosis induced by serum deprivation or kainic acid exposure. Protection requires pretreatment, consistent with the induction of a gene expression program, and is sustained for 3 days without the continued presence of EPO. EPO (0.3 units/ml) also protects hippocampal neurons against hypoxia-induced neuronal death through activation of extracellular signal-regulated kinases and protein kinase Akt-1/protein kinase B. The action of EPO is not limited to directly promoting cell survival, as EPO is trophic but not mitogenic in cultured neuronal cells. These data suggest that inhibition of neuronal apoptosis underlies short latency protective effects of EPO after cerebral ischemia and other brain injuries. The neurotrophic actions suggest there may be longer-latency effects as well. Evaluation of EPO, a compound established as clinically safe, as neuroprotective therapy in acute brain injury is further supported.

Image recognition: Visual grouping, recognition, and learning

Vision extracts useful information from images. Reconstructing the three-dimensional structure of our environment and recognizing the objects that populate it are among the most important functions of our visual system. Computer vision researchers study the computational principles of vision and aim at designing algorithms that reproduce these functions. Vision is difficult: the same scene may give rise to very different images depending on illumination and viewpoint. Typically, an astronomical number of hypotheses exist that in principle have to be analyzed to infer a correct scene description. Moreover, image information might be extracted at different levels of spatial and logical resolution dependent on the image processing task. Knowledge of the world allows the visual system to limit the amount of ambiguity and to greatly simplify visual computations. We discuss how simple properties of the world are captured by the Gestalt rules of grouping, how the visual system may learn and organize models of objects for recognition, and how one may control the complexity of the description that the visual system computes.

Autoimmunity to βIV spectrin in paraneoplastic lower motor neuron syndrome

Paraneoplastic neurological disorders may result from autoimmunity directed against antigens shared by the affected neurons and the associated cancer cells. We have recently reported the case of a woman with breast cancer and paraneoplastic lower motor neuron syndrome whose serum contained autoantibodies directed against axon initial segments and nodes of Ranvier of myelinated axons, including the axons of motoneurons. Here, we show that major targets of the autoantibodies of this patient are βIVΣ1 spectrin and βIV spectrin 140, two isoforms of the novel βIV spectrin gene, as well as a neuronal surface epitope yet to be identified. Partial improvement of the neurological symptoms following cancer removal was associated with a drastic reduction in the titer of the autoantibodies against βIV spectrin and nodal antigens in general, consistent with the autoimmune pathogenesis of the paraneoplastic lower motor neuron syndrome. The identification of βIV spectrin isoforms and surface nodal antigens as novel autoimmune targets in lower motor neuron syndrome provide new insights into the pathogenesis of this severe neurological disease.

Habitat e genoma: possibili adattamenti di H. pylori allo stomaco umano

Helicobacter pylori è un batterio patogeno che infetta e abita lo stomaco umano. La sua diffusione è ubiquitaria nel mondo ed esso è responsabile di varie patologie, sia gastriche che extra-gastriche. Vista l’estrema ostilità del suo habitat, H. pylori necessita di specifici adattamenti che lo rendono unico nella sua capacità di tollerare l’estrema acidità dello stomaco umano, oltre ad evitare la risposta immunitaria dell’ospite. In questa tesi verranno adottati degli approcci bioinformatici per cercare di individuare quali possano essere gli adattamenti e le caratteristiche del genoma di questo batterio correlati con la sopravvivenza nell’ambiente gastrico e l’adattamento all’ospite umano.

Rome, Italy, 1823 (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Nuova pianta di Roma Moderna, estratta dalla grande del Nolli corretta ed accresciuta de nomi delle contrade indicati al loro rispettivo sito in Roma; Pietro Ruga incise. It was published by Venanzio Monaldini Libraio e Cartolaro in 1823. Scale [ca. 1:9,120]. Covers Rome, Italy and Vatican City. The image inside the map neatline is georeferenced to the surface of the earth and fit to the "European Datum 1950 UTM Zone 33N" coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as roads, drainage, city districts, walls, gates, and fortifications, selected buildings, and more. Relief is shown by hachures. Includes index and inset plans: Pianta della Chiesa di S. Lorenzo fuori le mura -- Mausoleo di S. Costanza -- Pianta della Basilica di S. Paolo -- Pianta del Pantheon, degli avanzi delle Terme di Agrippa, e dé ruderi scoperti recentemente. This layer is part of a selection of digitally scanned and georeferenced historic maps from The Harvard Map Collection as part of the Imaging the Urban Environment project. Maps selected for this project represent major urban areas and cities of the world, at various time periods. These maps typically portray both natural and manmade features at a large scale. The selection represents a range of regions, originators, ground condition dates, scales, and purposes.

Rome, Italy, 1832 (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Pianta della citta di Roma : con la indicazione di tvtte le antichita e nvovi abbellimenti nell anno MDCCCXXXII, Pietro Ruga incise. It was published by Venanzio Monaldini libraio e cartolaro in 1832. Scale [ca. 1:5,066]. Covers Rome, Italy and Vatican City.The image inside the map neatline is georeferenced to the surface of the earth and fit to the "European Datum 1950 UTM Zone 33N" coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as roads, drainage, city districts, walls, gates, and fortifications, selected buildings, and more. Relief is shown by hachures. Includes indices and architectural engravings at left and right margins: Basilica di S. Giovanni -- Interno di S. Giovanni -- Basilica di S. Paolo -- Interno di S. Paolo -- Campidoglio Moderno -- Anfiteatro Favio -- Primaide di C. Cestio -- Foro Trajano -- Basilica di S. Pietro -- Interno di S. Pietro -- Basilica di S. M.a Maggiore -- Interno di S. M.a Maggiore -- Pantheon di Agrippa -- Interno del Pantheon -- Monte Cavallo -- Foro Romano. This layer is part of a selection of digitally scanned and georeferenced historic maps from The Harvard Map Collection as part of the Imaging the Urban Environment project. Maps selected for this project represent major urban areas and cities of the world, at various time periods. These maps typically portray both natural and manmade features at a large scale. The selection represents a range of regions, originators, ground condition dates, scales, and purposes.

The Proactive International Dimension and the Breakdown of Authoritarian Regimes

There is international consensus among scholars that democratic transitions are multicausal processes in which both internal and international variables are involved (Pridham 1991, 1995; Whitehead 1996; Schmitter 1996; Linz and Stepan 1996; Carothers 1999; Morlino and Magen 2008; Grilli di Cortona 2009). This chapter is limited, on the one hand, to the dependent variable consisting solely of the crisis/breakdown/transformation of non-democratic regimes in the Third Wave of democratization, and, on the other hand, to an independent variable identified solely with the international dimension of democratic transition. This factor, which can be termed the Proactive International Dimension (PID), specifically concerns that combination of actions or processes, produced by one or more international actors, that, intentionally or not, cause or contribute to the crisis/breakdown/transformation of a non-democratic regime.