A TNF-α Promoter Polymorphism Is Associated with Juvenile Onset Psoriasis and Psoriatic Arthritis

Tumor necrosis factor-α is considered to be one of the important mediators in the pathogenesis of psoriasis. A strong association of juvenile onset psoriasis with the major histocompatibility complex encoded HLA-Cw6 antigen has been reported but it is unclear whether Cw6 itself or a closely linked gene is involved in the pathogenesis. This study has focused on the association of promoter polymorphisms of the major histocompatibility complex encoded tumor necrosis factor-α gene with psoriasis and psoriatic arthritis. Tumor necrosis factor-α promoter polymorphisms were sought by sequence-specific oligonucleotide hybridization and by direct sequencing in Caucasian patients with juvenile onset psoriasis and with psoriatic arthritis and in healthy controls. A mutation at position −238 of the tumor necrosis factor-α promoter was present in 23 of 60 patients (38%; p < 0.0001; Pcorr < 0.008) with juvenile onset psoriasis and in 20 of 62 patients (32%; p < 0.0003; Pcorr < 0.03) with psoriatic arthritis, compared with seven of 99 (7%) Caucasian controls. There was a marked increase of homozygotes for this mutation in the psoriasis group. Another mutation at position −308 was found in similar proportions of patients and controls. Our study shows a strong association of the tumor necrosis factor-α promoter polymorphism at position −238 with psoriasis and psoriatic arthritis. Our findings suggest that this promoter polymorphism itself or a gene in linkage disequilibrium with tumor necrosis factor-α predispose to the development of psoriasis

Novel multiple sclerosis susceptibility loci implicated in epigenetic regulation.

We conducted a genome-wide association study (GWAS) on multiple sclerosis (MS) susceptibility in German cohorts with 4888 cases and 10,395 controls. In addition to associations within the major histocompatibility complex (MHC) region, 15 non-MHC loci reached genome-wide significance. Four of these loci are novel MS susceptibility loci. They map to the genes L3MBTL3, MAZ, ERG, and SHMT1. The lead variant at SHMT1 was replicated in an independent Sardinian cohort. Products of the genes L3MBTL3, MAZ, and ERG play important roles in immune cell regulation. SHMT1 encodes a serine hydroxymethyltransferase catalyzing the transfer of a carbon unit to the folate cycle. This reaction is required for regulation of methylation homeostasis, which is important for establishment and maintenance of epigenetic signatures. Our GWAS approach in a defined population with limited genetic substructure detected associations not found in larger, more heterogeneous cohorts, thus providing new clues regarding MS pathogenesis

Quantitative MR Neurography in Multifocal Motor Neuropathy and Amyotrophic Lateral Sclerosis

Background: The aim of this study was to assess the phenotype of multifocal motor neuropathy (MMN) and amyotrophic lateral sclerosis (ALS) in quantitative MR neurography. Methods: In this prospective study, 22 patients with ALS, 8 patients with MMN, and 10 healthy volunteers were examined with 3T MR neurography, using a high-resolution fat-saturated T2-weighted sequence, diffusion-tensor imaging (DTI), and a multi-echo T2-relaxometry sequence. The quantitative biomarkers fractional anisotropy (FA), radial and axial diffusivity (RD, AD), mean diffusivity (MD), cross-sectional area (CSA), T2-relaxation time, and proton spin density (PSD) were measured in the tibial nerve at the thigh and calf, and in the median, radial, and ulnar nerves at the mid-upper arm. Results: MMN showed a characteristic imaging pattern of decreased FA (p = 0.018), increased RD (p = 0.014), increased CSA (p p p = 0.025) in the upper arm nerves compared to ALS and controls. ALS patients did not differ from controls in any imaging marker, nor were there any group differences in the tibial nerve (p > 0.05). Conclusions: MMN shows a characteristic pattern of quantitative DTI and T2-relaxometry parameters in the upper-arm nerves, primarily indicating demyelination. Peripheral nerve changes in ALS seem to be below the detection level of current state-of-the-art quantitative MR neurography

Differential diagnosis of vacuolar myopathies in the NGS era

Altered autophagy accompanied by abnormal autophagic (rimmed) vacuoles detectable by light and electron microscopy is a common denominator of many familial and sporadic non‐inflammatory muscle diseases. Even in the era of next generation sequencing (NGS), late‐onset vacuolar myopathies remain a diagnostic challenge. We identified 32 adult vacuolar myopathy patients from 30 unrelated families, studied their clinical, histopathological and ultrastructural characteristics and performed genetic testing in index patients and relatives using Sanger sequencing and NGS including whole exome sequencing (WES). We established a molecular genetic diagnosis in 17 patients. Pathogenic mutations were found in genes typically linked to vacuolar myopathy (GNE, LDB3/ZASP, MYOT, DES and GAA), but also in genes not regularly associated with severely altered autophagy (FKRP, DYSF, CAV3, COL6A2, GYG1 and TRIM32) and in the digenic facioscapulohumeral muscular dystrophy 2. Characteristic histopathological features including distinct patterns of myofibrillar disarray and evidence of exocytosis proved to be helpful to distinguish causes of vacuolar myopathies. Biopsy validated the pathogenicity of the novel mutations p.(Phe55*) and p.(Arg216*) in GYG1 and of the p.(Leu156Pro) TRIM32 mutation combined with compound heterozygous deletion of exon 2 of TRIM32 and expanded the phenotype of Ala93Thr‐caveolinopathy and of limb‐girdle muscular dystrophy 2i caused by FKRP mutation. In 15 patients no causal variants were detected by Sanger sequencing and NGS panel analysis. In 12 of these cases, WES was performed, but did not yield any definite mutation or likely candidate gene. In one of these patients with a family history of muscle weakness, the vacuolar myopathy was eventually linked to chloroquine therapy. Our study illustrates the wide phenotypic and genotypic heterogeneity of vacuolar myopathies and validates the role of histopathology in assessing the pathogenicity of novel mutations detected by NGS. In a sizable portion of vacuolar myopathy cases, it remains to be shown whether the cause is hereditary or degenerative

Differential diagnosis of vacuolar myopathies in the NGS era

Altered autophagy accompanied by abnormal autophagic (rimmed) vacuoles detectable by light and electron microscopy is a common denominator of many familial and sporadic non‐inflammatory muscle diseases. Even in the era of next generation sequencing (NGS), late‐onset vacuolar myopathies remain a diagnostic challenge. We identified 32 adult vacuolar myopathy patients from 30 unrelated families, studied their clinical, histopathological and ultrastructural characteristics and performed genetic testing in index patients and relatives using Sanger sequencing and NGS including whole exome sequencing (WES). We established a molecular genetic diagnosis in 17 patients. Pathogenic mutations were found in genes typically linked to vacuolar myopathy (GNE, LDB3/ZASP, MYOT, DES and GAA), but also in genes not regularly associated with severely altered autophagy (FKRP, DYSF, CAV3, COL6A2, GYG1 and TRIM32) and in the digenic facioscapulohumeral muscular dystrophy 2. Characteristic histopathological features including distinct patterns of myofibrillar disarray and evidence of exocytosis proved to be helpful to distinguish causes of vacuolar myopathies. Biopsy validated the pathogenicity of the novel mutations p.(Phe55*) and p.(Arg216*) in GYG1 and of the p.(Leu156Pro) TRIM32 mutation combined with compound heterozygous deletion of exon 2 of TRIM32 and expanded the phenotype of Ala93Thr‐caveolinopathy and of limb‐girdle muscular dystrophy 2i caused by FKRP mutation. In 15 patients no causal variants were detected by Sanger sequencing and NGS panel analysis. In 12 of these cases, WES was performed, but did not yield any definite mutation or likely candidate gene. In one of these patients with a family history of muscle weakness, the vacuolar myopathy was eventually linked to chloroquine therapy. Our study illustrates the wide phenotypic and genotypic heterogeneity of vacuolar myopathies and validates the role of histopathology in assessing the pathogenicity of novel mutations detected by NGS. In a sizable portion of vacuolar myopathy cases, it remains to be shown whether the cause is hereditary or degenerative

Risk and course of COVID-19 in immunosuppressed patients with myasthenia gravis

Background Patients with myasthenia gravis (MG) are potentially prone for a severe COVID-19 course, but there are limited real-world data available on the risk associated with COVID-19 for patients with MG. Here, we investigate whether current immunosuppressive therapy (IST) influences the risk of SARS-CoV-2 infection and COVID-19 severity. Methods Data from the German myasthenia gravis registry were analyzed from May 2020 until June 2021 and included patient demographics, MG disease duration, comorbidities, current IST use, COVID-19 characteristics, and outcomes. Propensity score matching was employed to match MG patients with IST to those without, and multivariable binary logistic regression models were used to determine associations between IST with (1) symptomatic SARS-CoV-2 infection and (2) severe COVID-19 course, as measured by hospitalization or death. Results Of 1379 patients with MG, 95 (7%) patients (mean age 58 (standard deviation [SD] 18) presented with COVID-19, of which 76 (80%) received IST at time of infection. 32 patients (34%) were hospitalized due to COVID-19; a total of 11 patients (12%) died. IST was a risk factor for hospitalization or death in the group of COVID-19-affected MG patients (odds ratio [OR] 3.04, 95% confidence interval [CI] =1.02-9.06, p = 0.046), but current IST was not associated with a higher risk for SARS-CoV-2 infection itself. Discussion In this national MG cohort study, current IST use was a risk factor for a severe disease course of COVID-19 but not for SARS-CoV-2 infection itself. These data support the consequent implementation of effective strategies to prevent COVID-19 in this high-risk group

4-Deoxyaurone Formation in <i>Bidens ferulifolia</i> (Jacq.) DC

<div><p>The formation of 4-deoxyaurones, which serve as UV nectar guides in <i>Bidens ferulifolia</i> (Jacq.) DC., was established by combination of UV photography, mass spectrometry, and biochemical assays and the key step in aurone formation was studied. The yellow flowering ornamental plant accumulates deoxy type anthochlor pigments (6′-deoxychalcones and the corresponding 4-deoxyaurones) in the basal part of the flower surface whilst the apex contains only yellow carotenoids. For UV sensitive pollinating insects, this appears as a bicoloured floral pattern which can be visualized in situ by specific ammonia staining of the anthochlor pigments. The petal back side, in contrast, shows a faintly UV absorbing centre and UV absorbing rays along the otherwise UV reflecting petal apex. Matrix-free UV laser desorption/ionisation mass spectrometric imaging (LDI-MSI) indicated the presence of 9 anthochlors in the UV absorbing areas. The prevalent pigments were derivatives of okanin and maritimetin. Enzyme preparations from flowers, leaves, stems and roots of <i>B. ferulifolia</i> and from plants, which do not accumulate aurones e.g. <i>Arabidopsis thaliana</i>, were able to convert chalcones to aurones. Thus, aurone formation could be catalyzed by a widespread enzyme and seems to depend mainly on a specific biochemical background, which favours the formation of aurones at the expense of flavonoids. In contrast to 4-hydroxyaurone formation, hydroxylation and oxidative cyclization to the 4-deoxyaurones does not occur in one single step but is catalyzed by two separate enzymes, chalcone 3-hydroxylase and aurone synthase (catechol oxidase reaction). Aurone formation shows an optimum at pH 7.5 or above, which is another striking contrast to 4-hydroxyaurone formation in <i>Antirrhinum majus</i> L. This is the first example of a plant catechol oxidase type enzyme being involved in the flavonoid pathway and in an anabolic reaction in general.</p></div

Targeted transcript analysis in muscles from patients with genetically diverse congenital myopathies

Congenital myopathies are a group of early onset muscle diseases of variable severity often with characteristic muscle biopsy findings and involvement of specific muscle types. The clinical diagnosis of patients typically relies on histopathological findings and is confirmed by genetic analysis. The most commonly mutated genes encode proteins involved in skeletal muscle excitation–contraction coupling, calcium regulation, sarcomeric proteins and thin–thick filament interaction. However, mutations in genes encoding proteins involved in other physiological functions (for example mutations in SELENON and MTM1, which encode for ubiquitously expressed proteins of low tissue specificity) have also been identified. This intriguing observation indicates that the presence of a genetic mutation impacts the expression of other genes whose product is important for skeletal muscle function. The aim of the present investigation was to verify if there are common changes in transcript and microRNA expression in muscles from patients with genetically heterogeneous congenital myopathies, focusing on genes encoding proteins involved in excitation–contraction coupling and calcium homeostasis, sarcomeric proteins, transcription factors and epigenetic enzymes. Our results identify RYR1, ATPB2B and miRNA-22 as common transcripts whose expression is decreased in muscles from congenital myopathy patients. The resulting protein deficiency may contribute to the muscle weakness observed in these patients. This study also provides information regarding potential biomarkers for monitoring disease progression and response to pharmacological treatments in patients with congenital myopathies

HPLC chromatograms from incubation of enzyme preparations.

<p><i>Bidens ferulifolia</i> petals (a) and leaves (b), <i>Antirrhinum majus</i> petals (c) and leaves (d), <i>Arabidopsis thaliana</i> col-0 plants (e), <i>Tagetes erecta</i> petals (f), <i>Dianthus caryophyllus</i> petals (g), and <i>Petunia hybrida</i> petals (h) with butein and of enzyme preparations from <i>B. ferulifolia</i> petals (i) and <i>Antirrhinum majus</i> petals (j) with isoliquiritigenin.</p