Decreased water T2in fatty infiltrated skeletal muscles of patients with neuromuscular diseases

Myotonic dystrophies (DMs, the second most diffuse forms of muscular dystrophy, after Duchenne dystrophy) are genetically-based degenerative neuromuscular diseases exhibiting widely variable clinical features and characterized by myotonia (i.e., a prolonged contraction of skeletal muscles after short stimulation) and a delayed muscle relaxation after voluntary contraction. There are two form of DMs: the more severe DM1 (or Steinert’s disease), and the milder form DM2. The intranuclear accumulation of expanded RNAs is considered as the pathogenetic factor of DMs: the presence of these RNAs exerts a toxic action on cell function which essentially depends on the ectopic sequestration of nuclear protein factors involved in the processing of transcripts. The aim of this mini-symposium is to describe the genetic and cellular bases of DMs, showing how the results of basic research may provide important clues for both diagnosis and therapy.

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Rules of tissue packing involving different cell types: human muscle organization

10.1101/038968 ◽

2016 ◽

Author(s):

Daniel Sanchez-Gutierrez ◽

Aurora Saez ◽

Carmen Paradas ◽

Luis M. Escudero

Keyword(s):

Motor Neurons ◽

Skeletal Muscles ◽

Spatial Organization ◽

Biceps Brachii ◽

Relative Size ◽

Neuromuscular Diseases ◽

Cell Types ◽

Quadriceps Muscle ◽

Relative Distribution ◽

Mathematical Concepts

Natural packed tissues are assembled as tessellations of polygonal cells that do not leave empty spaces between them. They include the epithelial sheets and the skeletal muscles. Epithelia are formed by equivalent cells that change shape and organization through development. The skeletal muscles appear as a mosaic composed by two different types of cells: the slow and fast fibres that are determined by the identities of the motor neurons that innervate them. Their relative distribution is important for the muscle function and can be altered in some neuromuscular diseases. Little is known about how the spatial organization of fast and slow fibres is established and maintained. In this work we use computerized image analysis and mathematical concepts to capture the organizational pattern in two different healthy muscles: biceps brachii and quadriceps. Here we show that each type of muscle portrays a characteristic topological pattern that allows distinguishing between them. The biceps brachii muscle presents a particular arrange based on the different size of slow and fast fibres, contrary to the quadriceps muscle where an unbiased distribution exists. Our results indicate that the relative size of each cellular type imposes an intrinsic organization into the tissue. These findings establish a new framework for the analysis of packed tissues where two or more cell types exist.

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Functional state of motor units of skeletal muscles in chronic diseases of motoneurons and their axones

Neurology Bulletin ◽

10.17816/nb77703 ◽

1995 ◽

Vol XXVII (1-2) ◽

pp. 5-10

Author(s):

L. F. Kasatkina

Keyword(s):

Motor Neuron ◽

Chronic Diseases ◽

Functional State ◽

Skeletal Muscles ◽

Neuromuscular Diseases ◽

Motor Units ◽

Peripheral Motor ◽

Partial Compensation

Electromyographic examination of the potentials of motor units in 498 patients with different forms of peripheral motor neuron pathology allowed to distinguish electromyographic criteria of estimation of the denervationreinnervation processes. Determination of phases of full, partial compensation and of decompensation phase may be used for examination of pathogenesis of neuromuscular diseases, their diagnosis and assessment of their progress.

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In situ hybridization of myoglobin mRNA: results on the skeletal muscles of normal subjects and patients with neuromuscular diseases

Acta Neuropathologica ◽

10.1007/bf00369442 ◽

1993 ◽

Vol 86 (4) ◽

pp. 313-318 ◽

Cited By ~ 5

Author(s):

Takao Mitsui ◽

Hisaomi Kawai ◽

Takako Naruo ◽

Hiroshi Nishino ◽

Shiro Saito

Keyword(s):

In Situ Hybridization ◽

Skeletal Muscles ◽

Neuromuscular Diseases ◽

Normal Subjects

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Distinctive morphological and gene/protein expression signatures during myogenesis in novel cell lines from extraocular and hindlimb muscle

Physiological Genomics ◽

10.1152/physiolgenomics.00234.2004 ◽

2006 ◽

Vol 24 (3) ◽

pp. 264-275 ◽

Cited By ~ 32

Author(s):

John D. Porter ◽

Sheri Israel ◽

Bendi Gong ◽

Anita P. Merriam ◽

Jason Feuerman ◽

...

Keyword(s):

Protein Expression ◽

Cell Lines ◽

Skeletal Muscles ◽

Neuromuscular Diseases ◽

In Vitro Models ◽

Hindlimb Muscle ◽

Novel Traits ◽

Intrinsic Capacity ◽

Muscle Groups

Skeletal muscles are not created equal. The underutilized concept of muscle allotypes defines distinct muscle groups that differ in their intrinsic capacity to express novel traits when exposed to a facilitating extrinsic environment. Allotype-specific traits may have significance as determinants of the preferential involvement or sparing of muscle groups that is observed in a variety of neuromuscular diseases. Little is known, however, of the developmental mechanisms underlying the distinctive skeletal muscle allotypes. The lack of appropriate in vitro models, to dissociate the cell-autonomous and non-cell-autonomous mechanisms behind allotype diversity, has been a barrier to such studies. Here, we derived novel cell lines from the extraocular and hindlimb muscle allotypes and assessed their similarities and differences during early myogenesis using morphological and gene/protein expression profiling tools. Our data establish that there are fundamental differences in the transcriptional and cellular signaling pathways used by the two myoblast lineages. Taken together, these data show that myoblast lineage plays a significant role in the divergence of the distinctive muscle groups or allotypes.

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Phosphorylated TDP-43 aggregates in skeletal and cardiac muscle are a marker of myogenic degeneration in amyotrophic lateral sclerosis and various conditions

Acta Neuropathologica Communications ◽

10.1186/s40478-019-0824-1 ◽

2019 ◽

Vol 7 (1) ◽

Cited By ~ 7

Author(s):

Fumiaki Mori ◽

Mari Tada ◽

Tomoya Kon ◽

Yasuo Miki ◽

Kunikazu Tanji ◽

...

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Cardiac Muscle ◽

Skeletal Muscles ◽

Neuromuscular Diseases ◽

Iliopsoas Muscle ◽

Vacuolar Degeneration ◽

Cardiac Muscles ◽

The Central Nervous System ◽

Als Patients ◽

Lateral Sclerosis

Abstract Background Amyotrophic lateral sclerosis (ALS) is characterized pathologically by the occurrence of phosphorylated TDP-43 (pTDP-43)-immunoreactive neuronal and glial inclusions in the central nervous system. Recent studies have shown that pTDP-43 aggregates also occur in the skeletal muscles in a certain proportion of ALS patients. Aim The aim of this study was to clarify the distribution and incidence of pTDP-43 aggregates in the skeletal and cardiac muscles of patients with ALS, and also those of patients with neuromuscular diseases (NMDs) and non-NMDs. Material and methods Five regions of muscle (tongue, cervical muscle, diaphragm, iliopsoas muscle and heart) were examined histologically and immunohistochemically in patients with ALS (n = 30), NMDs (n = 13) and non-NMDs (n = 7). Results Two types of pTDP-43 aggregates were distinguishable morphologically: dense filamentous and short linear inclusions. These inclusions were found in at least one of the five muscle regions in all 30 cases of ALS; skeletal muscles in 28 cases and myocardium in 12. pTDP-43 aggregates were also found in 9 of 13 patients with NMDs, including myositis, muscular dystrophy and mitochondrial myopathy, as well as in 3 of 7 patients with non-NMDs. In ALS, pTDP-43 aggregates were most frequent in the diaphragm (19 cases). The mean density of pTDP-43 aggregates in ALS was significantly higher than that in NMDs and non-NMDs. In contiguous sections stained with hematoxylin and eosin and anti-pTDP-43, muscle fibers with dense filamentous inclusions demonstrated single-fiber atrophy with vacuolar degeneration. Conclusion The present findings indicate that pTDP-43 aggregates in skeletal and cardiac muscle are a myogenic pathological marker in multiple diseases including ALS.

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Inherited neuromuscular diseases in the mouse: a review of the literature

Arquivos de Neuro-Psiquiatria ◽

10.1590/s0004-282x1988000300011 ◽

1988 ◽

Vol 46 (3) ◽

pp. 298-307 ◽

Cited By ~ 2

Author(s):

Luiz Fernando Bleggi Torres

Keyword(s):

Peripheral Nerves ◽

Skeletal Muscles ◽

Animal Species ◽

Neuromuscular Disorders ◽

Scientific Information ◽

Neuromuscular Diseases ◽

Experimental Manipulation ◽

Laboratory Animals ◽

Motor End Plates ◽

Low Costs

There are several neuromuscular disorders affecting the human being. Most of these are poorly understood and lack an effective treatment. Due to the limitation of experimental manipulation in «anima nobili», inherited neuromuscular diseases in laboratory animals constitute a valuable source of scientific information. Amongst several animal species affected by neuromuscular disorders the house mouse is of particular interest because of its small size, short pregnancy and low costs of maintanence. In the present review 20 murine mutants with diseases affecting peripheral nerves, skeletal muscles and motor end-plates are tabulated. Genetic, clinical and pathological aspects are discussed aiming to provide information about these mutants which might be of great interest as animal models for human neuromuscular diseases.

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Distribution of c-protein isoforms in sarcomeres of developing chick skeletal muscle

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010010319x ◽

1988 ◽

Vol 46 ◽

pp. 226-227

Author(s):

D. A. Fischman ◽

J. E. Dennis ◽

T. Obinata ◽

H. Takano-Ohmuro

Keyword(s):

Skeletal Muscles ◽

Thick Filament ◽

Protein Isoforms ◽

Actin Binding ◽

Striated Muscles ◽

C Protein ◽

Sarcomeric Protein ◽

Thick Filaments ◽

Cross Bridges ◽

Bridge Bearing

C-protein is a 150 kDa protein found within the A bands of all vertebrate cross-striated muscles. By immunoelectron microscopy, it has been demonstrated that C-protein is distributed along a series of 7-9 transverse stripes in the medial, cross-bridge bearing zone of each A band. This zone is now termed the C-zone of the sarcomere. Interest in this protein has been sparked by its striking distribution in the sarcomere: the transverse repeat between C-protein stripes is 43 nm, almost exactly 3 times the 14.3 nm axial repeat of myosin cross-bridges along the thick filaments. The precise packing of C-protein in the thick filament is still unknown. It is the only sarcomeric protein which binds to both myosin and actin, and the actin-binding is Ca-sensitive. In cardiac and slow, but not fast, skeletal muscles C-protein is phosphorylated. Amino acid composition suggests a protein of little or no αhelical content. Variant forms (isoforms) of C-protein have been identified in cardiac, slow and embryonic muscles.

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The effect of ionophore A23178 on the α-actinin crosslinks in the z-band of frog skeletal muscle: An EM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142396 ◽

1986 ◽

Vol 44 ◽

pp. 154-155

Author(s):

F.T. Llados ◽

V. Krlho ◽

G.D. Pappas

Keyword(s):

Muscle Damage ◽

Transmitter Release ◽

Skeletal Muscles ◽

Calcium Uptake ◽

Muscle Membrane ◽

Frog Skeletal Muscle ◽

Ach Release ◽

Sustained Action ◽

Calcium Deposits ◽

Intense Stimulation

It Is known that Ca++ enters the muscle fiber at the junctional area during the action of the neurotransmitter, acetylcholine (ACh). Pappas and Rose demonstrated that following Intense stimulation, calcium deposits are found In the postsynaptic muscle membrane, Indicating the existence of calcium uptake In the postsynaptic area following ACh release. In addition to this calcium uptake, when mammal Ian skeletal muscles are exposed to a sustained action of the neurotransmitter, muscle damage develops. These same effects, l.e., Increased transmitter release, calcium uptake and finally muscle damage, can be obtained by Incubating the muscle with lonophore A23178.

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