17 research outputs found

    On the origin of neutron magnetic scattering in anti-site disordered Sr2FeMoO6 double perovskites

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    Anti-site disordering in Sr2FeMoO6 double perovskites (containing Mo atoms at Fe positions, and viceversa) has recently been shown to have a dramatic influence in their magnetic and magnetotransport properties. In the present study, two polycrystalline Sr2FeMoO6 samples showing different degrees of anti-site disorder (a nominally 'ordered' sample with 70% of cationic ordering and a nominally 'disordered' sample with 18% of cationic ordering) have been examined by magnetic measurements and neutron powder diffraction (NPD) techniques in the 15-500K temperature range. Our main finding is that the 'disordered' sample exhibits a strong magnetic scattering (noticeable even at 500K), comparable to that displayed by the 'ordered' one below TC= 415 K. For the 'disordered' sample, the magnetic scattering exhibited on low angle Bragg positions, is not to be ascribed to a (non-existent) ferrimagnetic ordering: our results suggest that it originates upon naturally-occurring groups of Fe cations in which strong antiferromagnetic (AFM) Fe-O-Fe superexchange interactions are promoted, similar to those existing in the LaFeO3 perovskite. These Fe groups are not magnetically isolated, but coupled by virtue of Fe-O-Mo AFM interactions, which maintain the long-range coherence of this AFM structure. Susceptibility measurements confirm the presence of AFM interactions below 770 K.Comment: 30 pages, 11 figures, to be published in PR

    Association between Change in Normal Appearing White Matter Metabolites and Intrathecal Inflammation in Natalizumab-Treated Multiple Sclerosis

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    Background: Multiple sclerosis (MS) is associated not only with focal inflammatory lesions but also diffuse pathology in the central nervous system (CNS). Since there is no firm association between the amount of focal inflammatory lesions and disease severity, diffuse pathology in normal appearing white matter (NAWM) may be crucial for disease progression. Immunomodulating treatments for MS reduce the number of focal lesions, but possible effects on diffuse white matter pathology are less studied. Furthermore, it is not known whether intrathecal levels of inflammatory or neurodegenerative markers are associated with development of pathology in NAWM. Methods: Quantitative proton magnetic resonance spectroscopy (1H-MRS) was used to investigate NAWM in 27 patients with relapsing MS before and after one year of treatment with natalizumab as well as NAWM in 20 healthy controls at baseline. Changes in 1H-MRS metabolite concentrations during treatment were also correlated with a panel of intrathecal markers of inflammation and neurodegeneration in 24 of these 27 patients. Results: The group levels of 1H-MRS metabolite concentrations were unchanged pre-to posttreatment, but a pattern of high magnitude correlation coefficients (r = 0.43–0.67, p&lt;0.0005–0.03) were found between changes in individual metabolite concentrations (total creatine and total choline) and levels of pro-inflammatory markers (IL-1β and CXCL8). Conclusions: Despite a clinical improvement and a global decrease in levels of inflammatory markers in cerebrospinal fluid during treatment, high levels of pro-inflammatory CXCL8 and IL-1β were associated with an increase in 1H-MRS metabolites indicative of continued gliosis development and membrane turnover in NAWM.funding agencies|Swedish Society of Neurologically Disabled||Swedish Society of Medicine||National Research Council (VR/NT)||University Hospital of Linkoping||County Council of Ostergotland||Teva||Biogen Idec||</p

    Effect of self-managed lifestyle treatment on glycemic control in patients with type 2 diabetes

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    The lack of effective, scalable solutions for lifestyle treatment is a global clinical problem, causing severe morbidity and mortality. We developed a method for lifestyle treatment that promotes self-reflection and iterative behavioral change, provided as a digital tool, and evaluated its effect in 370 patients with type 2 diabetes (ClinicalTrials.gov identifier: NCT04691973). Users of the tool had reduced blood glucose, both compared with randomized and matched controls (involving 158 and 204 users, respectively), as well as improved systolic blood pressure, body weight and insulin resistance. The improvement was sustained during the entire follow-up (average 730 days). A pathophysiological subgroup of obese insulin-resistant individuals had a pronounced glycemic response, enabling identification of those who would benefit in particular from lifestyle treatment. Natural language processing showed that the metabolic improvement was coupled with the self-reflective element of the tool. The treatment is cost-saving because of improved risk factor control for cardiovascular complications. The findings open an avenue for self-managed lifestyle treatment with long-term metabolic efficacy that is cost-saving and can reach large numbers of people

    Trajectories of cognitive processing speed and physical disability over 11 years following initiation of a first multiple sclerosis disease-modulating therapy

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    Background: We analysed the COMparison Between All immunoTherapies for Multiple Sclerosis (NCT03193866), a Swedish nationwide observational study in relapsing-remitting multiple sclerosis (RRMS), to identify trajectories of processing speed and physical disability after disease-modulating therapy (DMT) start. Methods: Using a group-modelling approach, we assessed trajectories of processing speed with oral Symbol Digit Modalities Test (SDMT) and physical disability with Expanded Disability Status Scale, from first DMT start among 1645 patients with RRMS followed during 2011-2022. We investigated predictors of trajectories using group membership as a multinomial outcome and calculated conditional probabilities linking membership across the trajectories. Results: We identified 5 stable trajectories of processing speed: low SDMT scores (mean starting values=29.9; 5.4% of population), low/medium (44.3; 25.3%), medium (52.6; 37.9%), medium/high (63.1; 25.8%) and high (72.4; 5.6%). We identified 3 physical disability trajectories: no disability/stable (0.8; 26.8%), minimal disability/stable (1.6; 58.1%) and moderate disability (3.2; 15.1%), which increased to severe disability. Older patients starting interferons were more likely than younger patients starting rituximab to be on low processing speed trajectories. Older patients starting teriflunomide, with more than one comorbidity, and a history of pain treatment were more likely to belong to the moderate/severe physical disability trajectory, relative to the no disability one. There was a strong association between processing speed and physical disability trajectories. Conclusions: In this cohort of actively treated RRMS, patients' processing speed remained stable over the years following DMT start, whereas patients with moderate physical disability deteriorated in physical function. Nevertheless, there was a strong link between processing speed and disability after DMT start

    Predictors of patient-reported fatigue symptom severity in a nationwide multiple sclerosis cohort

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    Background: Fatigue is a debilitating symptom of multiple sclerosis (MS), but its relation to sociodemographic and disease-related characteristics has not been investigated in larger studies. The objectives of this study were to evaluate predictors of self-reported fatigue in a Swedish nationwide register-based MS cohort.Methods: Using a repeated cross-sectional design, we included 2,165 persons with relapsing-remitting and secondary progressive MS with one or multiple Fatigue Scale for Motor and Cognitive Functions (FSMC) scores, which was modelled using multivariable linear regressions for multiple predictors.Results: Only associations to expanded disability status scale (EDSS) and Symbol Digit Modalities Test (SDMT) were considered clinically meaningful among MS-associated characteristics in our main model; compared to mild disability (EDSS 0-2.5), those with severe disability (EDSS &amp;gt;= 6) scored 17.6 (95% CI 13.1-22.2) FSMC points higher, while the difference was 10.7 (95% CI 8.0-13.4) points for the highest and lowest quartiles of SDMT. Differences between highest and lowest quartiles of health-related quality of life (HRQoL) instruments were even greater and considered clinically meaningful; EuroQoL Visual Analogue Scale (EQ-VAS) 31.9 (95% CI 29.9-33.8), Multiple Sclerosis Impact Scale (MSIS-29) psychological component 35.6 (95% CI 33.8-37.4) and MSIS-29 physical component 45.5 (95% CI 43.7-47.4).Conclusion: Higher self-reported fatigue is associated with higher disability level and worse cognitive processing speed, while associations to other MS-associated characteristics including MS type, line of disease modifying therapy (DMT), MS duration, relapse and new cerebral lesions are weak. Furthermore, we found a strong correlation between high fatigue rating and lower ratings on health-related quality of life instruments.Funding Agencies|Patient-Centered Outcomes Research Institute (PCORI) Award [MS-1511-33196]; Swedish Research Council [2020-02700, TF 2016-01355]; Swedish Research Council for Health, Working Life, and Welfare [2020-0115]; NEURO Sweden</p

    Clinical and CSF data at baseline and at follow-up after one year of natalizumab treatment.

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    <p>Median values are given and range within parenthesis. n = 27 unless stated otherwise. p refers to Wilcoxon signed rank test comparing baseline and follow-up.</p>a<p>n = 25 since lumbar puncture was not done in two patients.</p>b<p>n = 24,</p>c<p>n = 23,</p>d<p>n = 22 (n was reduced from 25 due to technical errors or lack of sample volume).</p><p>Abbreviations: CSF = cerebrospinal fluid; EDSS = Expanded Disability Status Scale; MSSS = Multiple Sclerosis Severity Score; MSIS-29 = Multiple Sclerosis Impact Scale; SDMT = Symbol Digit Modalities Test; wbc = white blood cell; MBP = myelin basic protein; NFL = neurofilament light protein; GFAP = glial fibrillary acidic protein; T-tau = total tauprotein; P-tau = phosphorylated tauprotein; N = normal reference values; NA = not applicable.</p
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