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Query: UMLS:C0026850 (muscular dystrophy)
 5,870 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The dimensions of myonuclei and satellite cell nuclei in Duchenne's muscular dystrophy (DMD), polymyositis, and normal controls were compared in order to determine whether differences in satellite cell populations (previously reported by these and other authors) could be attributable to changes in the relative dimensions, thereby biasing the counts. The nuclei were measured directly from semithin resin sections using computerized measuring techniques, thereby avoiding errors due to photographic enlargement. In both the control and polymyositic groups, the satellite cell nuclei (8.30 microns and 8.81 microns respectively) were significantly shorter than the myonuclei (11.75 microns and 13.00 micron). Dystrophic myonuclei (10.98 microns) were significantly shorter than polymyositic myonuclei, but dystrophic satellite cell nuclei (11.62 microns) were significantly longer than both polymyositic and normal control satellite cell nuclei. The mean nuclear area in transverse sections was significantly greater in both myopathies than in the control material for both myonuclei and satellite cell nuclei. Myonuclei were significantly larger than satellite cell nuclei in all groups. When the values for the lengths of the nuclei were used to adjust previous estimates of satellite cell populations, it was found that earlier conclusions were still valid, i.e., that there is a significant increase in the number of satellite cells in the dystrophic muscle fibre population.
Anat Rec 1988 Sep
PMID:A quantitative study of myonuclear and satellite cell nuclear size in Duchenne's muscular dystrophy, polymyositis and normal human skeletal muscle. 318 87

The pattern of postnatal growth and development of skeletal muscle in mdx mice was studied by light and transmission electron microscopy and by autoradiography and was compared with that in their normal age-matched controls at 4 and 32 weeks of age. The muscle weights of both the extensor digitorum longus (EDL) and soleus muscles of mdx mice were significantly greater than those in control mice at both ages. Body weights of male and female mdx mice were also increased over controls up to 12 weeks of age. At 4 weeks, both the EDL and soleus muscles exhibited focal areas of degeneration, necrosis, and regeneration of centrally nucleated extrafusal fibers resulting in a wide range of fiber sizes. By 32 weeks, the majority of fibers in both muscles were centrally nucleated, and focal areas of recent regeneration were observed. By electron microscopy, the course of macrophage infiltration into areas of degenerating fibers and the ongoing regeneration of myofibers within redundant cylinders of external lamina were noted. This pattern was frequent in 4-week-old mdx muscles and was present to a lesser degree at 32 weeks. A notable lack of both adipose tissue infiltration and fibrotic change in the endomysium were observed in muscles at both ages. Autoradiograms of muscles from 4-week-old mdx mice injected with tritiated thymidine showed an increased proportion of labeled sublaminal nuclei at 24 and 48 hours after injection compared to controls. At 32 weeks of age, labeling of nuclei in muscles of mdx mice was also greater than in controls, but was reduced compared to muscle labeling in 4-week-old mdx mice. The observed features of mdx muscle tissue suggest that this animal model is more applicable to the study of regeneration dynamics than to Duchenne-type human muscular dystrophy.
Anat Rec 1987 Nov
PMID:Electron microscopic and autoradiographic characterization of hindlimb muscle regeneration in the mdx mouse. 342 43

The intramembrane particles on plasma membranes of erythrocytes of Syrian hamsters afflicted with hereditary muscular dystrophy were compared to those from normal controls by freeze-fracture analysis. The reduced number of particles in both fracture faces of dystrophic erythrocyte plasmalemmae, as compared to that of control red cells, was found to be highly significant (P = .001). Results of this study therefore, support the concept of a generalized membrane defect (abnormality) in muscular dystrophy.
Anat Rec 1986 Jun
PMID:Freeze-fracture analysis of intramembrane particles of erythrocytes from normal and dystrophic hamsters. 372 15

A condition of Jersey calves involving kyphosis and lordosis is described. Four calves originating from three farms, all the progeny of one bull, were necropsied. The only significant finding was a myopathy mainly affecting sublumbar muscles. The lesions were not consistent with white muscle disease or of any known myopathy affecting Jersey calves. It is likely that this condition represents a primary muscular dystrophy of genetic origin.
Vet Rec 1985 Dec 07
PMID:Kyphosis in Jersey calves. 408 37

Outbreaks of alopecia with unusually high morbidity occurred among calves reared on milk substitutes on two unrelated farms in Suffolk. On one farm alopecia occurred for three consecutive years; during the winter of 1981-82 there were also clinical signs of muscular dystrophy among the same calves. On the second farm calves with alopecia also showed signs of muscular dystrophy. The apparent relationship between alopecia and milk substitute feeding is discussed together with the possible involvement of vitamin E.
Vet Rec 1983 Apr 30
PMID:Alopecia in calves associated with milk substitute feeding. 686 7

Experiments have been carried out to examine the submandibular glands in mice with hereditary muscular dystrophy. Radioimmunoassay data confirm biological studies which show that submandibular glands in mice with muscular dystrophy contain less nerve growth factor (NGF) than glands of normal animals. Male dystrophics have half as much submandibular NGF as unafflicted mice, while females have only 10% of control levels. Gel filtration and electrophoretic studies detect no differences in the molecular properties of NGF in gland extracts from normal and dystrophic mice. Furthermore, NGF from both sources show equal activity in the sensory ganglion bioassay. Together, these results suggest that NGF deficits in submandibular glands of dystrophic mice are not due to measurement artifacts arising from alterations in the structure of the molecule. Morphological studies have uncovered a cytological basis for chemical deficits within submandibular glands of dystrophic mice. Stereological analysis of light and electron microscopic sections revealed that growth factor containing granular tubule cells (GTC) take up a smaller portion of the total gland volume, are smaller in size, and contain fewer secretory granules than comparable cells in glands from controls. Furthermore, the ultrastructure of GTC in dystrophic animals suggests that the cells are less active in producing secretory protein than GTC in glands from normal animals. These results are consistent with the idea that growth factor deficits arise from cellular abnormalities in the granular tubule segment of the gland.
Anat Rec 1981 Jun
PMID:Submandibular glands in mice with muscular dystrophy: studies with nerve growth factor. 727 Sep 19

A case of primary progressive muscular dystrophy in a labrador dog is described. The differential diagnosis with respect to certain muscular and nervous disorders is discussed. The possibility of the hereditary nature of the disease is indicated.
Vet Rec 1980 Apr 12
PMID:Primary progressive muscular dystrophy in the dog. 737 86

Two muscle biopsies from the gluteus medius and semitendinosus muscles of a six-month-old male standardbred trotter with clinical signs of hypertrophy and hypertonicity, and an electromyogram showing myotonic discharges in the glutei, semitendinosus and semimembranosus muscles, were examined by histological, histochemical and ultrastructural methods. Histologically, the main findings were variations in fibre size and shape, vacuolisation, hyalinisation and the splitting of fibres, an increase in the numbers of internal nuclei, infiltration by connective tissue and fat, hypertrophy and the predominance of type I fibres, and clusters of one type of fibre. These histological results resembled those in human muscular dystrophy.
Vet Rec 1994 Aug 13
PMID:Dystrophy-like myopathy in a foal. 798 45

Among a group of dysphagic dogs the bouvier des Flandres was overrepresented. The results of a clinical examination, contrast videofluorography and electromyography of the pharyngeal, laryngeal and oesophageal muscles were similar in all the bouviers, and a histological examination of tissues from 10 of them revealed muscular dystrophy as the cause of the dysphagia. A study of the affected dogs' pedigrees revealed that they were descendants of one closely related group of ancestors, and that the inbreeding levels for this ancestor group were higher than in a control population of 136 bouviers. The homozygosity due to inbreeding for this ancestor group was higher in the affected dogs than in the control dogs, but the homozygosity due to all other ancestry was equal in the two groups. The relative risk of developing dysphagia-associated muscular dystrophy was up to 16 times greater in these bouviers, depending on the level of inbreeding for the closely related ancestor group.
Vet Rec 1994 Apr 23
PMID:Dysphagia-associated muscular dystrophy: a familial trait in the bouvier des Flandres. 804 16

Dystrophin is a high molecular weight protein localized under the sarcolemma of normal extrafusal muscle fibers but absent in skeletal muscle of Duchenne muscular dystrophy patients and mdx mice. Muscle spindles in the soleus of 32-week-old normal and age-matched mdx mice were examined by immunocytochemical methods to determine the localization of dystrophin in polar and equatorial regions of the intrafusal fibers. Spindles were serially sectioned in transverse and longitudinal planes, and were double-labelled with an antibody to dystrophin and with an antibody to a 200 kD neurofilament protein, which revealed their sensory innervation. By fluorescence microscopy, intrafusal fibers in the soleus of mdx mice were deficient in dystrophin throughout their lengths, whereas their sensory nerve terminals stained intensely with the nerve-specific antibody and appeared unaltered in dystrophy. In the normal soleus, intrafusal fibers displayed a regional variability in the distribution of dystrophin. Polar regions of bag and chain fibers exhibited a peripheral rim of sarcolemmal staining equivalent to that seen in the neighboring extrafusal fibers. Dystrophin labelling in equatorial regions of normal intrafusal fibers, however, showed dystrophin-deficient segments alternating in a spiral fashion with positive-staining domains along the sarcolemma. Double-labelling for dystrophin and neurofilament protein showed that these dystrophin-deficient sites were subjacent to the annulospiral sensory nerve wrappings terminating on the intrafusal fibers. These findings suggest that dystrophin is not an integral part of the subsynaptic sensory membrane in equatorial regions of normal intrafusal fibers and thus is not directly related to sensory signal transduction. The complete absence of this protein in mdx intrafusal fibers indicates that these fibers exhibit the same primary defect in muscular dystrophy as seen in the extrafusal fibers. However, because of their small diameters, capsular investment, and relatively low tension outputs, dystrophic intrafusal fibers may be less prone to the sarcolemmal membrane disruption that is characteristic of extrafusal fibers in this disorder.
Anat Rec 1993 Apr
PMID:Distribution of dystrophin and neurofilament protein in muscle spindles of normal and Mdx-dystrophic mice: an immunocytochemical study. 846 85


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