0000000000617730
AUTHOR
Christiane Schneider
Familial mixed congenital myopathy with rigid spine phenotype
We describe a father and daughter with a rigid spine syndrome and proximal myopathy. The index patient was a 42-year-old man, who died from respiratory failure after a lifelong, slowly progressive proximal myopathy and a rigid spine phenotype. This was morphologically characterized by cytoplasmic bodies, increased desmin, features of reducing-body myopathy, and sarcoplasmic and intranuclear tubulofilamentous inclusions. These cases are characterized by an early onset and possibly autosomal-dominant inheritance, with associated complex structural hallmarks of both desmin-related and inclusion body myopathies. Together they may be defined as a complex mixed congenital myopathy with a rigid sp…
Expression of the Acetylcholine Receptor α-Subunit Gene is Associated with Paraneoplastic Myasthenia Gravis in Mixed Thymoma
Myasthenia gravis (MG) is an autoimmune disease caused by autoantibodies against the acetylcholine receptor (AChR) at the neuromuscular junction [1]. The muscular AChR has been extensively characterized [2], but the etiology of MG is still obscure. Whether the muscular AChR or another (auto)antigen plays a role during the initiation of MG is unknown [3]. The muscular AChR is a pentameric ion channel composed of four different subunits. The α-subunit contains the acetylcholine binding site and the main epitopes recognized by MG autoantibodies [2]. The human muscle AChR α-subunit exists as two isoforms, P3A- and P3A+ [4]. This is a result of alternative splicing of the P3A exon located betwee…
Low Levels of Acetylcholine Receptor Delta-Subunit Message and Protein in Human Thymus Suggests the Occurrence of ‘Triplet Receptors’ in Thymic Myoid Cells
Myasthenia gravis (MG) is an autoimmune disease caused by autoantibodies against the acetylcholine receptor (AChR) at the neuromuscular junction [1]. The muscular AChR has been extensively characterized [2], but whether the muscular AChR plays a role during the initiation of MG is unknown [3]. The muscular AChR is a pentameric ion channel composed of 4 different subunits [2, 4]. The fetal AChR expressed during intrauterine life and after denervation of adult muscle exhibits an α2βδγ composition, while the adult AChR expressed after birth in innervated muscle exhibits an α2βδγ composition [4]. The α-subunit contains the main epitopes recognized by MG autoantibodies [2]. The human muscle AChR…