Broken R-symmetry and defect conformal manifolds

Just as exactly marginal operators allow to deform a conformal field theory along the space of theories known as the conformal manifold, appropriate operators on conformal defects allow for deformations of the defects. A setup that guarantees exactly marginal defect operators in theories with extended supersymmetry are defects that break the R-symmetry group. In that case the conformal manifold is the symmetry breaking coset and its Zamolodchikov metric is expressed as the two point function of the exactly marginal operator. As the Riemann tensor on the conformal manifold can be expressed as an integrated correlator of the marginal operators, we find an exact relation to the curvature of the coset space.We examine in detail the case of the 1/2 BPS Maldacena-Wilson loop in $\mathcal{N}=4$ SYM, which breaks $SO(6)\to SO(5)$ and the 1/2 BPS surface operator of the 6d $\mathcal{N}=(2,0)$ theory with $SO(5)\to SO(4)$ breaking. We verify this identity against known 4-point functions, previously derived from AdS/CFT and the conformal bootstrap.Comment: 19 page

Restless legs syndrome/Willis–Ekbom disease prevalence in beta thalassemia patients

Purpose Both beta thalassemia and restless legs syndrome (RLS) patients share some common pathophysiological characteristics related to iron handling. In the present study, the aim was to explore the prevalence of RLS as well as to explore potential association between the syndrome and various quality of life-related parameters in a sample of beta thalassemia patients. Methods One hundred fourteen (age 40 ± 11 yr, 59 M/55F) beta thalassemia patients participated in this cross-sectional descriptive study. Patients were screened for RLS based on the international RLS study group diagnostic criteria as well as a battery of validated questionnaires. Results The prevalence of RLS in this sample of beta thalassemia patients was zero. The quality of life score was low (78 ± 18). Iron levels were within normal range (191 ± 66 mcg/dL) while ferritin levels were high as expected (1836 ± 225 ng/dL). Conclusions Our sample of patients comes from central Greece where the prevalence of RLS in the general population is 4% while in renal failure patients is 27%. To our surprise, there was no presence of RLS among this sample of beta thalassemia patients. The adequate levels of iron and ferritin often seen in these patients could be the reason of the absence of RLS symptoms

Effects of controlled dehydration on sleep quality and quantity: A polysomnographic study in healthy young adults

Dehydration is associated with several alternations in body homeostasis involving both physiological and mental aspects. In addition some studies have reported a negative effect of dehydration on subjectively assessed sleep-related parameters. The aim of the current study was to examine for the first time the effect of controlled dehydration on sleep quality and quantity using the gold-standard method of polysomnography. Twelve healthy male volunteers participated in this study (23.4 ± 0.8 years). Participants performed an in-house full polysomnographic assessment in two different occasions taking place in random order: (i) in a dehydrated state; and (ii) in a euhydrated state. In the dehydration scenario, the participants were allowed to consume only 1.25 L of non-caffeinated fluids, while during the euhydrated state participants had to drink at least 3 L of non-caffeinated fluids during the last 24 hr before the polysomnographic study. Urine specific gravity was assessed by refractrometry on collection day in order to assess hydration status. Participants who did not fulfil the hydration criteria were rescheduled. All participants successfully completed the two polysomnographic studies without any complaints or adverse effects reported. No significant differences were found in any of the examined indices of sleep quality and quantity between the dehydration and euhydration scenarios (p > .05). This is the first study to show that controlled mild dehydration does not seem to affect sleep quality and quantity in young healthy adults. More research is necessary to further verify these conclusions and assess whether other parameters are involved in the manifestation of sleep disturbances

Restless legs syndrome is contributing to fatigue and low quality of life levels in hemodialysis patients

AIM: To examine whether hemodialysis (HD) patients with restless legs syndrome (RLS) are subjects of greater fatigue and impaired quality of life (QoL) compared to HD patients without RLS. METHODS: Eighty five stable HD patients participated in this study. According to their RLS status, the patients were divided into the RLS group (n = 23) and the non-RLS group (n = 62). QoL, fatigue, sleep quality, daily sleepiness and depression symptoms were assessed by using various questionnaires. Finally, biochemical parameters including iron, ferritin, hemoglobin, hematocrit and parathormone were assessed. RESULTS: The HD patients with RLS scored worse in all the questionnaires used in the study (P < 0.05). The patients with RLS were more likely to receive the HD therapy on the morning shift, whilst 43.5% of the RLS patients reported to experience the RLS symptoms also during HD. The severity of RLS was correlated with fatigue, depression score and sleep quality (P < 0.05). CONCLUSION: HD patients with RLS are subject to lower QoL related parameters and greater fatigue compared to HD patients without RLS. RLS should be successfully managed in order to improve the QoL of the sufferers

Restless legs syndrome in Multiple Sclerosis patients: a contributing factor for fatigue, impaired functional capacity, and diminished health-related quality of life

Objectives Restless legs syndrome (RLS) symptoms are common in Multiple Sclerosis (MS) patients. The aim of the current study was to examine for the first time whether RLS could affect the functional capacity and various contributing parameters related to quality of life and fatigue in MS patients. Methods According to their RLS status, 50 relapsing-remitting MS patients were divided into the RLS (n = 10) and non-RLS groups (n = 40). Specific questionnaires were used in order to assess the health-related quality of life (HRQoL), fatigue levels, sleep quality, daily sleepiness, and depression symptoms of the patients. Functional capacity was examined using a battery of functional tests. Total body and visceral fat levels were assessed via bioelectrical impedance analyzers. Results Sleep quality, depression, fatigue, and HRQoL levels were found to be significantly worse in the patients with RLS compared to their free-RLS counterparts (P < 0.05). In addition, patients with RLS were found to exhibit further impairments in their performance in various functional tests related mainly with strength levels of lower extremities (P < 0.05). Finally, the patients with RLS were found to have significantly higher both total and trunk fat levels compared to patients without RLS (P < 0.05). A strong correlation was observed between the severity of RLS symptoms, sleep quality, fatigue, and QoL levels. Discussion It seems that RLS contributes even further to impairments on sleep quality, fatigue, functional capacity, and therefore HRQoL levels in relapsing-remitting MS patients, whilst for the first time a link between high fat levels has been revealed

Evidence of Increased Muscle Atrophy and Impaired Quality of Life Parameters in Patients with Uremic Restless Legs Syndrome

BACKGROUND: Restless Legs Syndrome is a very common disorder in hemodialysis patients. Restless Legs Syndrome negatively affects quality of life; however it is not clear whether this is due to mental or physical parameters and whether an association exists between the syndrome and parameters affecting survival. METHOD#ENTITYSTARTX003BF;LOGY/PRINCIPAL FINDINGS: Using the Restless Legs Syndrome criteria and the presence of Periodic Limb Movements in Sleep (PLMS/h >15), 70 clinically stable hemodialysis patients were assessed and divided into the RLS (n = 30) and non-RLS (n = 40) groups. Physical performance was evaluated by a battery of tests: body composition by dual energy X ray absorptiometry, muscle size and composition by computer tomography, while depression symptoms, perception of sleep quality and quality of life were assessed through validated questionnaires. In this cross sectional analysis, the RLS group showed evidence of thigh muscle atrophy compared to the non-RLS group. Sleep quality and depression score were found to be significantly impaired in the RLS group. The mental component of the quality of life questionnaire appeared significantly diminished in the RLS group, reducing thus the overall quality of life score. In contrast, there were no significant differences between groups in any of the physical performance tests, body and muscle composition. CONCLUSIONS: The low level of quality of life reported by the HD patients with Restless Legs Syndrome seems to be due mainly to mental health and sleep related aspects. Increased evidence of muscle atrophy is also observed in the RLS group and possibly can be attributed to the lack of restorative sleep

MEIS1 and BTBD9: genetic association with restless leg syndrome in end stage renal disease

Background: Restless legs syndrome (RLS) is a sleep related movement disorder that occurs both in an idiopathic form and in symptomatic varieties. RLS is a frequent and distressing comorbidity in end stage renal disease (ESRD). For idiopathic RLS (iRLS), genetic risk factors have been identified, but their role in RLS in ESRD has not been investigated yet. Therefore, a caseecontrol association study of these variants in ESRD patients was performed. Methods: The study genotyped 10 iRLS associated variants at four loci encompassing the genes MEIS1, BTBD9, MAP2K5/SKOR1, and PTPRD, in two independent caseecontrol samples from Germany and Greece using multiplex PCR and MALDI-TOF (matrix assisted laser desorption/ionisation time-of-flight) mass spectrometry. Statistical analysis was performed as logistic regression with age and gender as covariates. For the combined analysis a CochraneManteleHaenszel test was applied. Results: The study included 200 RLS-positive and 443 RLS-negative ESRD patients in the German sample, and 141 and 393 patients, respectively, in the Greek sample. In the German sample, variants in MEIS1 and BTBD9 were associated with RLS in ESRD (Pnom≤0.004, ORs 1.52 and 1.55), whereas, in the Greek sample, there was a trend for association to MAP2K5/SKOR1 and BTBD9 (Pnom≤0.08, ORs 1.41 and 1.33). In the combined analysis including all samples, BTBD9 was associated after correction for multiple testing (Pcorrected=0.0013, OR 1.47). Conclusions: This is the first demonstration of a genetic influence on RLS in ESRD patients with BTBD9 being significantly associated. The extent of the genetic predisposition could vary between different subgroups of RLS in ESRD

Effect of exercise training and dopamine agonists in patients with uremic restless legs syndrome: A six-month randomized, partially double-blind, placebo-controlled comparative study

© 2013 The Authors. Published by BMC. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1186/1471-2369-14-194Background: Restless Legs Syndrome is very common in hemodialysis patients however there are no comparative studies assessing the effectiveness of a non-pharmacological treatment to a classical treatment on parameters related to syndromes' severity and quality of life. Methods. In this randomized, partially double blind, placebo controlled trial, thirty two hemodialysis patients with restless legs syndrome were randomly assigned into three groups: 1) the exercise training group (N = 16), 2) the dopamine agonists group (ropinirole 0.25 mg/d) (N = 8) and 3) the placebo group (N = 8). The intervention programs lasted 6 months. Restless Legs Syndrome severity was assessed using the international severity scale, physical performance by a battery of tests, muscle size and composition by computed tomography, body composition by Dual Energy X Ray Absorptiometry, while depression score, sleep quality, daily sleepiness and quality of life were assessed through questionnaires. Results: Exercise training and dopamine agonists were effective in reducing syndrome's symptoms by 46% (P = 0.009) and 54% (P = 0.001) respectively. Within group changes revealed that both approaches significantly improved quality of life (P 0.05) in various tests. Between group changes detect significant improvements with both exercise and dopamine agonists in depression score (P = 0.003), while only the dopamine agonist treatment was able to significantly improve sleep quality, compared to exercise and placebo (P = 0.016). Conclusions: A 6-month exercise training regime was as effective as a 6-month low dosage dopamine agonist treatment in reducing restless legs syndrome symptoms and improving depression score in uremic patients. Further research is needed in order to show whether a combination treatment could be more beneficial for the amelioration of RLS. Trial registration. NCT00942253. © 2013 Giannaki et al.; licensee BioMed Central Ltd.This study was supported by the National and Community Funds of the Greek Ministry of Development-General Secretariat of Research and Technology and by the European Social Fund.Published versio

Experience with rituximab in scleroderma: results from a 1-year, proof-of-principle study

Objective. To assess the efficacy of rituximab (RTX) in SSc