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Patterns of multiple sclerosis (MS) plaques by magnetic resonance imaging (MRI) and proton-MR spectroscopy (1H-MRS) evaluation
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Epidemiology of pediatric multiple sclerosis: incidence, prevalence and susceptibility risk factors
No full textThe contribution of (1)H-magnetic resonance spectroscopy in defining the pathophysiology of multiple sclerosis
No full textProton magnetic resonance spectroscopy ((1)H-MRS) is considered a suitable
investigation technique for obtaining in vivo information on pathological changes
in multiple sclerosis (MS) brain. The main betabolites identified are
choline-containing compounds, creatine, N-acetylaspartate (NAA), lactate, mobile
lipids, myo-inositol, glutamate and glutamine. Proton spectra may be acquired
from localized volumes of interest on single MS lesions or from the entire brain
by (1)H-MRS imaging. An increase of choline and lipids (markers of demyelination)
and the presence of lactate (marker of acute inflammatory reaction) have been
demonstrated in active Gd-enhancing MS plaques. A reduction of NAA (marker of
neuronal or axonal damage) has been found in inactive MS lesions. The recent
evidence of an early NAA decrease in active plaques and in normal appearing white
matter suggests that axonal damage is an early event in the evolution of
demyelinating lesions. The correlation between NAA decrease and clinical
disability conforms that axonal damage has important functional consequences, and
indicates that the prevention of irreversible axonal loss might be a major target
for the design and the timing of therapeutical strategies
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