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Aims: Diagnosis of idiopathic inflammatory myopathies (IIM) is based on morphological characteristics and the evaluation of disease‐related proteins. However, although broadly applied, substantial bias is imposed by the respective methods, observers and individual staining approaches. We aimed to quantify the protein levels of major histocompatibility complex (MHC)‐1, (MHC)‐2 and intercellular adhesion molecule (ICAM)‐1 using an automated morphometric method to mitigate bias. Methods: Double immunofluorescence staining was performed on whole muscle sections to study differences in protein expression in myofibre and endomysial vessels. We analysed all IIM subtypes including dermatomyositis (DM), anti‐synthetase syndrome (ASyS), inclusion body myositis (IBM), immune‐mediated‐necrotising myopathy (IMNM), dysferlinopathy (DYSF), SARS‐CoV‐2 infection and vaccination‐associated myopathy. Biopsies with neurogenic atrophy (NA) and normal morphology served as controls. Bulk RNA‐Sequencing (RNA‐Seq) was performed on a subset of samples. Results: Our study highlights the significance of MHC‐1, MHC‐2 and ICAM‐1 in diagnosing IIM subtypes and reveals distinct immunological profiles. RNASeq confirmed the precision of our method and identified specific gene pathways in the disease subtypes. Notably, ASyS, DM and SARS‐CoV‐2‐associated myopathy showed increased ICAM‐1 expression in the endomysial capillaries, indicating ICAM‐1‐associated vascular activation in these conditions. In addition, ICAM‐1 showed high discrimination between different subgroups with high sensitivity and specificity. Conclusions: Automated morphometric analysis provides precise quantitative data on immune‐associated proteins that can be integrated into our pathophysiological understanding of IIM. Further, ICAM‐1 holds diagnostic value for the detection of IIM pathology. [ABSTRACT FROM AUTHOR]

This article explores the distribution and composition of the ferritin complex in the adult brain and its connection to neuroferritinopathy (NF), a type of neurodegeneration with brain iron accumulation (NBIA). NF is characterized by symptoms like movement disturbances and tremors. The study identifies a novel variant in the ferritin heavy chain gene (FTH1) that is associated with NF and provides insights into the role of ferritin in both healthy and diseased brains. [Extracted from the article]

Dermatomyositis (DM) is a systemic idiopathic inflammatory disease affecting skeletal muscle and skin, clinically characterized by symmetrical proximal muscle weakness and typical skin lesions. Recently, myositis‐specific autoantibodies (MSA) became of utmost importance because they strongly correlate with distinct clinical manifestations and prognosis. Antibodies against transcription intermediary factor 1γ (TIF‐1γ) are frequently associated with increased risk of malignancy, a specific cutaneous phenotype and limited response to therapy in adult DM patients. Anti‐Mi‐2 autoantibodies, in contrast, are typically associated with classic DM rashes, prominent skeletal muscle weakness, better therapeutic response and prognosis, and less frequently with cancer. Nevertheless, the sensitivity of autoantibody testing is only moderate, and alternative reliable methods for DM patient stratification and prediction of cancer risk are needed. To further investigate these clinically distinct DM subgroups, we herein analyzed 30 DM patients (n = 15 Mi‐2+ and n = 15 TIF‐1 γ+) and n = 8 non‐disease controls (NDC). We demonstrate that the NanoString technology can be used as a very sensitive method to clearly differentiate these two clinically distinct DM subgroups. Using the nCounter PanCancer Immune Profiling Panel™, we identified a set of significantly dysregulated genes in anti‐TIF‐1γ+ patient muscle biopsies including VEGFA, DDX58, IFNB1, CCL5, IL12RB2, and CD84. Investigation of type I IFN‐regulated transcripts revealed a striking type I interferon signature in anti‐Mi‐2+ patient biopsies. Our results help to stratify both subgroups and predict, which DM patients require an intensified diagnostic procedure and might have a poorer outcome. Potentially, this could also have implications for the therapeutic approach. [ABSTRACT FROM AUTHOR]

Introduction: Small fiber neuropathies (SFN) are associated with a reduction in quality of life. In adults, epidermal nerve fiber density (END) analysis is recommended for the diagnosis of SFN. In children, END assessment is not often performed. We analyzed small nerve fiber innervation to elucidate the potential diagnostic role of skin biopsies in young patients with pain.Methods: Epidermal nerve fiber density and sudomotor neurite density (SND) were assessed in skin biopsies from 26 patients aged 7 to 20 years (15 female patients) with unexplained chronic pain. The results were compared with clinical data.Results: Epidermal nerve fiber density was abnormal in 50% and borderline in 35% of patients. An underlying medical condition was found in 42% of patients, including metabolic, autoimmune, and genetic disorders.Discussion: Reduction of epidermal nerve fibers can be associated with treatable conditions. Therefore, the analysis of END in children with pain may help to uncover a possible cause and guide potential treatment options. [ABSTRACT FROM AUTHOR]

Purpose Phantoms are often used to assess MR system stability in multicenter studies. Postmortem brain phantoms best replicate human brain anatomy, allowing for a combined assessment of the MR system and software chain for data analysis. However, a wash-out of fixative fluid affecting T1 values and thus T1-weighted sequences such as magnetization-prepared 180 degrees radiofrequency pulses and rapid gradient-echo (MP-RAGE) has been reported for brain phantoms, hampering their immediate use. The purpose of this study was the creation of anatomical data that provide the characteristics of conventional data while avoiding this artifact. Theory and Methods Two brain phantoms were scanned at several time points, acquiring conventional MP-RAGE data and quantitative T1 and proton density (PD) maps. Assuming a suitable cutoff value T1cut, synthetic MP-RAGE data were created from these maps, being T1-weighted for T1 > T1cut to reduce fluid signal in the sulci, but PD-weighted for T1 < T1cut for artifact suppression. Results A time-dependent artifact was observed in the T1 but not in the PD maps. The temporal stability of the synthetic data was greatly improved as compared to the conventional data. Conclusion The proposed method enables anatomical imaging of postmortem brain phantoms, avoiding artifacts induced by the wash-out of fixative fluid, and thus achieving high signal stability shortly after fixation. Magn Reson Med 77:1115-1123, 2017. © 2016 International Society for Magnetic Resonance in Medicine [ABSTRACT FROM AUTHOR]

Noonan syndrome with multiple lentigines (NSML) frequently manifests with hypertrophic cardiomyopathy (HCM). Recently, it was demonstrated that mTOR inhibition reverses HCM in NSML mice. We report for the first time on the effects of treatment with a rapamycin analog in an infant with LS and malignant HCM. In the boy, progressive HCM was diagnosed during the first week of life and a diagnosis of NSML was established at age 20 weeks by showing a heterozygous Q510E mutation in PTPN11. Immunoblotting with antibodies against pERK, pAkt, and pS6RP in fibroblasts demonstrated enhanced Akt/mTOR pathway activity. Because of the patient's critical condition, everolimus therapy was started at age 24 weeks and continued until heart transplantation at age 36 weeks. Prior to surgery, heart failure improved from NYHA stage IV to II and brain natriuretic peptide values decreased from 9,600 to <1,000 pg/ml, but no reversal of cardiac hypertrophy was observed. Examination of the explanted heart revealed severe hypertrophy and myofiber disarray with extensive perivascular fibrosis. These findings provide evidence that Akt/mTOR activity is enhanced in NSML with HCM and suggest that rapamycin treatment could principally be feasible for infantile NSML. The preliminary experiences made in this single patient indicate that therapy should start early to prevent irreversible cardiac remodelling. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Biotin-thiamine-responsive basal ganglia disease ( BTBGD) is a potentially treatable disorder caused by mutations in the SLC19A3 gene, encoding the human thiamine transporter 2. Manifestation of BTBGD as acute encephalopathy triggered by a febrile infection has been frequently reported, but the underlying mechanisms are not clear. We investigated a family with two brothers being compound heterozygous for the SLC19A3 mutations p.W94R and p.Q393*fs. Post-mortem analysis of the brain of one brother showed a mixture of acute, subacute and chronic changes with cystic and necrotic lesions and hemorrhage in the putamen, and hemorrhagic lesions in the caudate nucleus and cortical layers. SLC19A3 expression was substantially reduced in the cortex, basal ganglia and cerebellum compared with an age-matched control. Importantly, exposure of fibroblasts to stress factors such as acidosis or hypoxia markedly upregulated SLC19A3 in control cells, but failed to elevate SLC19A3 expression in the patient's fibroblasts. These results demonstrate ubiquitously reduced thiamine transporter function in the cerebral gray matter, and neuropathological alterations similar to Wernicke's disease in BTBGD. They also suggest that episodes of encephalopathy are caused by a substantially reduced capacity of mutant neuronal cells to increase SLC19A3 expression, necessary to adapt to stress conditions. [ABSTRACT FROM AUTHOR]