University of Perugia

About: University of Perugia is a education organization based out in Perugia, Umbria, Italy. It is known for research contribution in the topics: Population & Large Hadron Collider. The organization has 13365 authors who have published 39516 publications receiving 1265601 citations. The organization is also known as: Universitá degli Studi di Perugia & Universita degli Studi di Perugia.

Signaling Pathways in Exosomes Biogenesis, Secretion and Fate

Abstract: Exosomes are small extracellular vesicles (30–100 nm) derived from the endosomal system, which have raised considerable interest in the last decade. Several studies have shown that they mediate cell-to-cell communication in a variety of biological processes. Thus, in addition to cell-to-cell direct interaction or secretion of active molecules, they are now considered another class of signal mediators. Exosomes can be secreted by several cell types and retrieved in many body fluids, such as blood, urine, saliva and cerebrospinal fluid. In addition to proteins and lipids, they also contain nucleic acids, namely mRNA and miRNA. These features have prompted extensive research to exploit them as a source of biomarkers for several pathologies, such as cancer and neurodegenerative disorders. In this context, exosomes also appear attractive as gene delivery vehicles. Furthermore, exosome immunomodulatory and regenerative properties are also encouraging their application for further therapeutic purposes. Nevertheless, several issues remain to be addressed: exosome biogenesis and secretion mechanisms have not been clearly understood, and physiological functions, as well as pathological roles, are far from being satisfactorily elucidated.

Frontal lobe dysfunction in Parkinson's disease: prognostic value for dementia?

Abstract: The purpose of this longitudinal study was to investigate if the presence of frontal motor deficits in parkinsonians without signs of global intellectual impairment may have a predictive value for the development of a progressive dementing process during the course of the illness. An examination of the higher level of motor organization, using skills thought to depend upon the integrity of the frontal regions, was performed by 30 parkinsonian patients who did not present any signs of general intellectual impairment. According to their performance, as compared with controls, they were divided into two subgroups: those with and those without frontal dysfunctions. After a mean period of 4 years, a second neuropsychological examination was carried out to assess any eventual change of mental status. The results suggest that frontal dysfunctions may be observed several years before the appearance of generalized intellectual impairment and may be considered one of the predictive factors for development of dementia in Parkinson’s disease. Careful consideration of these defects during examination of motor abilities may be of value in the clinical management of parkinsonian patients.

Constraints on the Galactic Halo Dark Matter from Fermi-LAT Diffuse Measurements

Abstract: We have performed an analysis of the diffuse gamma-ray emission with the Fermi Large Area Telescope (LAT) in the Milky Way halo region, searching for a signal from dark matter annihilation or decay. In the absence of a robust dark matter signal, constraints are presented. We consider both gamma rays produced directly in the dark matter annihilation/decay and produced by inverse Compton scattering of the e +/e - produced in the annihilation/decay. Conservative limits are derived requiring that the dark matter signal does not exceed the observed diffuse gamma-ray emission. A second set of more stringent limits is derived based on modeling the foreground astrophysical diffuse emission using the GALPROP code. Uncertainties in the height of the diffusive cosmic-ray halo, the distribution of the cosmic-ray sources in the Galaxy, the index of the injection cosmic-ray electron spectrum, and the column density of the interstellar gas are taken into account using a profile likelihood formalism, while the parameters governing the cosmic-ray propagation have been derived from fits to local cosmic-ray data. The resulting limits impact the range of particle masses over which dark matter thermal production in the early universe is possible, and challenge the interpretation of the PAMELA/Fermi-LAT cosmic ray anomalies as the annihilation of dark matter.

Efficacy and Safety of Anticoagulant Treatment in Acute Cardioembolic Stroke A Meta-Analysis of Randomized Controlled Trials

Abstract: Background and Purpose— The role of anticoagulant treatment for acute cardioembolic stroke is uncertain. We performed an updated meta-analysis of all randomized trials to obtain the best estimates of the efficacy and safety of anticoagulants for the initial treatment of acute cardioembolic stroke. Methods— Using electronic and manual searches of the literature, we identified randomized trials comparing anticoagulants (unfractionated heparin or low-molecular-weight heparin or heparinoids), started within 48 hours, with other treatments (aspirin or placebo) in patients with acute ischemic cardioembolic stroke. Two reviewers independently selected studies and extracted data on study design, quality, and clinical outcomes, including death or disability, all strokes, recurrent ischemic stroke, and cerebral symptomatic bleeding. Odds ratios for individual outcomes were calculated for each trial and data from all the trials were pooled using the Mantel-Haenszel method. Results— Seven trials, involving 4624 patients with acute cardioembolic stroke, met the criteria for inclusion. Compared with other treatments, anticoagulants were associated with a nonsignificant reduction in recurrent ischemic stroke within 7 to 14 days (3.0% versus 4.9%, odds ratio 0.68, 95% CI: 0.44 to 1.06, P =0.09, number needed to treat=53), a significant increase in symptomatic intracranial bleeding (2.5% versus 0.7%, odds ratio 2.89; 95% CI: 1.19 to 7.01, P =0.02, number needed to harm=55), and a similar rate of death or disability at final follow up (73.5% versus 73.8%, odds ratio 1.01; 95% CI: 0.82 to 1.24, P =0.9). Conclusions— Our findings indicate that in patients with acute cardioembolic stroke, early anticoagulation is associated with a nonsignificant reduction in recurrence of ischemic stroke, no substantial reduction in death and disability, and an increased intracranial bleeding.