University of Siena

About: University of Siena is a education organization based out in Siena, Italy. It is known for research contribution in the topics: Population & Cancer. The organization has 12179 authors who have published 33334 publications receiving 1008287 citations. The organization is also known as: Università degli studi di Siena & Universita degli studi di Siena.

Association between pathological and MRI findings in multiple sclerosis

Abstract: Pathological evaluation is the gold standard for identifying processes related to multiple sclerosis that explain disease manifestations, and for guiding the development of new treatments. However, there are limitations to the techniques used, including the small number of donors available, samples often representing uncommon cases, and impossibility of follow-up. Correlative studies have demonstrated that MRI is sensitive to the different pathological substrates of multiple sclerosis (inflammation, demyelination, and neuro-axonal loss). The role of MRI in evaluating other pathological processes, such as leptomeningeal involvement, central vein and rim of lesions, microstructural abnormalities, iron accumulation, and recovery mechanisms, has been investigated. Although techniques used for quantifying pathological processes in different regions of the CNS have advanced diagnosis and monitoring of disease course and treatment of multiple sclerosis, new perspectives and questions have emerged, including how different pathological processes interact over the disease course and when remyelination might occur. Addressing these questions will require longitudinal studies using MRI in large cohorts of patients with different phenotypes.

Speckle-tracking echocardiography: A new technique for assessing myocardial function

Abstract: Speckle-tracking echocardiography has recently emerged as a quantitative ultrasound technique for accurately evaluating myocardial function by analyzing the motion of speckles identified on routine 2-dimensional sonograms. It provides non-Doppler, angle-independent, and objective quantification of myocardial deformation and left ventricular systolic and diastolic dynamics. By tracking the displacement of the speckles during the cardiac cycle, strain and the strain rate can be rapidly measured offline after adequate image acquisition. Data regarding the feasibility, accuracy, and clinical applications of speckle-tracking echocardiography are rapidly accumulating. This review describes the fundamental concepts of speckle-tracking echocardiography, illustrates how to obtain strain measurements using this technique, and discusses their recognized and developing clinical applications.

Variable Very High Energy Gamma-ray Emission from the Microquasar LS I +61 303.

Abstract: Microquasars are binary star systems with relativistic radio-emitting jets. They are potential sources of cosmic rays and can be used to elucidate the physics of relativistic jets. We report the detection of variable gamma-ray emission above 100 gigaelectron volts from the microquasar LS I 61 + 303. Six orbital cycles were recorded. Several detections occur at a similar orbital phase, which suggests that the emission is periodic. The strongest gamma-ray emission is not observed when the two stars are closest to one another, implying a strong orbital modulation of the emission or absorption processes.