1,721,167 research outputs found
Impact of restless legs syndrome and iron deficiency on attention-deficit/hyperactivity disorder in children
Objective: increasing evidence suggests a significant comorbidity between attention-deficit/hyperactivity disorder (ADHD) and restless legs syndrome (RLS). Iron deficiency may underlie common pathophysiological mechanisms in subjects with ADHD plus RLS (ADHD+RLS). To date, the impact of iron deficiency, RLS and familial history of RLS on ADHD severity has been scarcely examined in children. These issues are addressed in the present study.Methods: serum ferritin levels, familial history of RLS (diagnosed using National Institutes of Health (NIH) criteria) and previous iron supplementation in infancy were assessed in 12 ADHD+RLS children, 10 ADHD children and 10 controls. RLS was diagnosed using NIH-specific pediatric criteria, and ADHD severity was assessed using the Conners’ Parent Rating scale.Results: ADHD symptom severity was higher, although not significantly, in children with ADHD+RLS compared to ADHD. The mean serum ferritin levels were significantly lower in children with ADHD than in the control group (p<0.0005). There was a trend for lower ferritin levels in ADHD+RLS subjects versus ADHD. Both a positive family history of RLS and previous iron supplementation in infancy were associated with more severe ADHD scores.Conclusions: children with ADHD and a positive family history of RLS appear to represent a subgroup particularly at risk for severe ADHD symptoms. Iron deficiency may contribute to the severity of symptoms. We suggest that clinicians consider assessing children with ADHD for RLS, a family history of RLS, and iron deficienc
Idiopathic REM sleep behavior disorder and neurodegenerative risk: To tell or not to tell to the patient? How to minimize the risk?
Most people with idiopathic REM sleep behavior disorder (iRBD) have an underlying synucleinopathy, mainly Parkinson's disease (PD) or dementia with Lewy bodies, with median conversion time of 4-9 y from iRBD diagnosis and of 11-16 y from symptom onset. Subtle signs and imaging tests indicate concomitant neurodegeneration in widespread brain areas. Risk factor studies suggest that iRBD patients may have prior head injury, occupational farming, pesticide exposure, low education level and possibly more frequent family history of dream-enactment behavior (but not of PD), plus unexpected risk factors (smoking, ischemic heart disease and inhaled corticosteroid use). Unlike PD, caffeine and smoking appear not to have a protective role. Prior depression and antidepressant use may be early neurodegenerative signs rather than exclusively causative factors. Age, hyposmia, impaired color vision, abnormal dopaminergic imaging, mild cognitive impairment and possibly sleepiness, may identify patients at greater risk of more rapid conversion. The consensus is to generally disclose the neurodegenerative risk to patients (with the caveat that phenoconversion and its temporal course remain uncertain in individuals without "soft neurodegenerative signs" and those under 50 y of age), to suggest a healthy lifestyle and to take part in prospective cohort studies in anticipation of eventual neuroprotective trials
Does postural rigidity decrease during REM sleep without Atonia in Parkinson disease?
Study Objectives: Rigidity is a muscle hypertonia typical of Parkinson disease (PD), whereas rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by abnormally increased muscle tone during REM sleep (REM sleep without atonia) and enacting dream behaviors. Because movements are not bradykinetic during RBD in patients with PD, we investigated whether the background, wake postural rigidity is attenuated during REM sleep without atonia, in absence of movement. Methods: The amplitude of levator menti (postural muscle) electromyographic activity during relaxed evening wakefulness (considered as reference) and sleep (N2, N3, atonic REM sleep, and quiet REM sleep without atonia) was measured in 20 patients with PD (with and without RBD), 10 patients with idiopathic RBD patients and 10 healthy subjects. Results: The chin tone amplitude progressively decreased from wake to N2, N3, and atonic REM sleep in the four groups, but the highest amplitude was observed in PD patients with RBD during atonic REM sleep. Furthermore, chin muscle tone amplitude did not attenuate from wake to REM sleep without atonia in patients with both PD and RBD but dramatically attenuated (by 40% on average) in patients with idiopathic RBD. Conclusions: The high amplitude of chin muscle tone in PD with RBD (but not in idiopathic RBD) during REM sleep with and without atonia suggests that both PD-related hypertonia and RBD-related enhanced muscle tone coexist during REM sleep, together affecting chin muscle tone. Consequently, some rapid RBD movements likely start against a rigid postural tone
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
Variations on the Author
“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Attenuation of obstructive sleep apnea and overnight rostral fluid shift by physical activity
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