To gain a deeper understanding of skeletal muscle function in younger age and aging in elderly, identification of molecular signatures regulating these functions under physiological conditions is needed. Although molecular studies of healthy muscle have been conducted on adults and older subjects, there is a lack of research on infant muscle in terms of combined morphological, transcriptomic and proteomic profiles. To address this gap of knowledge, we performed RNA sequencing (RNA-seq), tandem mass spectrometry (LC-MS/MS), morphometric analysis and assays for mitochondrial maintenance in skeletal muscle biopsies from both, infants aged 4-28 months and adults aged 19-65 years.
View Article and Find Full Text PDFInclusion body myositis (IBM) is unique across the spectrum of idiopathic inflammatory myopathies (IIM) due to its distinct clinical presentation and refractoriness to current treatment approaches. One explanation for this resistance may be the engagement of cell-autonomous mechanisms that sustain or promote disease progression of IBM independent of inflammatory activity. In this study, we focused on senescence of tissue-resident cells as potential driver of disease.
View Article and Find Full Text PDFPurpose Of Review: Myotonic dystrophy type 2 (DM2) is a genetic disorder belonging to the spectrum of myotonic dystrophies. DM2 is characterized by progressive muscle weakness, wasting and muscle pain (myalgia), but can also affect many other organ systems. In this review, we provide an updated overview on the research literature on DM2 with a focus on the management of multisystemic involvement and atypical clinical phenotypes.
View Article and Find Full Text PDFObjective: The molecular characteristics of sporadic inclusion body myositis (sIBM) have been intensively studied, and specific patterns on the cellular, protein and RNA level have emerged. However, these characteristics have not been studied in the context of HIV-associated IBM (HIV-IBM). In this study, we compared clinical, histopathological, and transcriptomic patterns of sIBM and HIV-IBM.
View Article and Find Full Text PDFGenetic diagnosis of facioscapulohumeral muscular dystrophy (FSHD) remains a challenge in clinical practice as it cannot be detected by standard sequencing methods despite being the third most common muscular dystrophy. The conventional diagnostic strategy addresses the known genetic parameters of FSHD: the required presence of a permissive haplotype, a size reduction of the D4Z4 repeat of chromosome 4q35 (defining FSHD1) or a pathogenic variant in an epigenetic suppressor gene (consistent with FSHD2). Incomplete penetrance and epistatic effects of the underlying genetic parameters as well as epigenetic parameters (D4Z4 methylation) pose challenges to diagnostic accuracy and hinder prediction of clinical severity.
View Article and Find Full Text PDFInclusion body myositis (IBM) is the most prevalent idiopathic inflammatory myopathy (IIM) affecting older adults. The pathogenic hallmark of IBM is chronic inflammation of skeletal muscle. At present, we do not classify IBM into different sub-entities, with the exception perhaps being the presence or absence of the anti-cN-1A-antibody.
View Article and Find Full Text PDFBackground: Both hereditary transthyretin (ATTRv) amyloidosis and wildtype transthyretin (ATTRwt) amyloidosis can be associated with neurological diseases such as carpal tunnel syndrome and polyneuropathy. While ATTRv amyloidosis has been extensively studied, to date little is known about neurological complications of ATTRwt amyloidosis. In particular, the prevalence, pattern and extent of polyneuropathy and autonomic dysfunction has not been adequately investigated in the context of ATTRwt amyloidosis.
View Article and Find Full Text PDFBackground: There have been numerous classification systems to diagnose corresponding myositis subtypes and select appropriate therapeutic measures. However, the lack of a broad consensus on diagnostic criteria has led to clinical uncertainties. The objective of this study was to compare two commonly used dermatomyositis-classification systems regarding their clinical practicability and to point out their specific advantages and disadvantages.
View Article and Find Full Text PDFThree consecutive skeletal muscle biopsies during a several months time-frame, showing different degrees of neutral lipid storage. This is highlighted by Oil-red-O stains (D, E, F) and electron microscopy (G, H, I). Note the impact on mitochondrial morphology with so called 'parking lots (K, L).
View Article and Find Full Text PDFWe present not-yet-seen multimodal images of a 55-year-old female patient with isolated atrial amyloidosis (IAA) who clinically suffered from multiple atrial arrhythmias and heart failure symptoms with preserved left ventricular ejection fraction. We aim to show structural and functional abnormalities detected by electrophysiological voltage mapping, cardiac magnetic resonance imaging (MRI) [cMRI; atrial strain measurements, late gadolinium enhancement (LGE) visualization], and Tc-DPD scintigraphy. Bipolar voltage mapping performed during two electrophysiological procedures showed diffuse left atrial low-voltage areas (bipolar < 0.
View Article and Find Full Text PDFChronic hepatitis C virus (HCV) infection is a highly prevalent systemic disease, which can cause a variety of neurological complications. The HCV-associated symptoms can be differentiated into central and peripheral nervous systems as well as the musculature. Important pathomechanisms are HCV-associated autoimmunity (e.
View Article and Find Full Text PDFHereditary transthyretin amyloidosis (hATTR amyloidosis) is a multisystemic disease usually presenting in a mixed neurological and cardiological phenotype. We present a case of hATTR amyloidosis associated with Leu55Arg mutation causing a form of familial oculo-leptomeningeal amyloidosis. Two brothers and their mother presented with severe autonomic neuropathy, loss of visual acuity and lepto-meningeal involvement.
View Article and Find Full Text PDFThe efficacy and safety of interferon-free therapies for hepatitis C virus (HCV) infection have been reported. Considering the accumulating evidence for a direct central nervous system infection by HCV, we aim to evaluate the effect of direct acting antivirals (DAA) therapy on cognitive function in HCV patients. We conducted a longitudinal analysis of the cognitive performance of 22 patients (8 HCV+, 14 HCV+/HIV+) who completed neuropsychological testing at baseline and at week 12 after DAA therapy.
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