Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0231528 (myalgia)
 6,565 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

194 clinical, laboratory, electrophysiologic, histological, histochemical and immunohistochemical parameters were studied through statistical analysis in 112 cases of Duchenne muscular dystrophy (DMD) and in 26 cases of Becker muscular dystrophy (BMD). It was found a significant statistical difference (p < 0.05) between the two groups concerning the age of evaluation, beginning of symptoms, difficulty in walking, running, climbing and going downstairs, frequent falling down, support to walk, localized muscle pain, stopping climb stairs, and inability to walk. Muscle biopsy showed statistically significant (p < 0.05) differences between the two groups regarding the intensity of connective tissue and focal adipose tissue proliferation, presence of diffuse rounded atrophic and angulated fibers, diffuse hypertrophic and splitting fibers. There were also differences regarding excessive internal fibers nuclei, hypertrophic types 1 and 2 fibers, angulated atrophic fibers and focal increasing in the NADH-TR, angulated atrophic fibers in non-specific esterase, and accumulated NBT in the periphery of fibers in succinic dehidrogenase. Isolatedly muscle biopsy gave the correct diagnosis in 52.7% of DMD cases and in 69.2% of BMD cases. Dystrophin detection by immunofluorescence (60 cases) showed: absence in 87.0% of fibers in DMD cases, and sarcolemmal membrane discontinuites in all BMD cases. The muscle biopsy diagnosis had an agreement with the dystrophin results in 82.6% of DMD cases and 71.4% of BMD cases.
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PMID:[Early differentiation between Duchenne and Becker muscular dystrophy: clinical, laboratory, electrophysiology, histochemical, and immunohistochemical study of 138 cases]. 130 51

Animal models have proven very useful in furthering insight into a number of muscle diseases. Studies of ethanol-fed rats are being used to understand the pathogenetic mechanisms underlying acute and chronic myopathy induced by ethanol. Several animal species, including mice, dogs, and cats, develop X-linked muscular dystrophies, which have genetic defects identical to those of Duchenne muscular dystrophy. As in the human disease, these animals lack dystrophin. They are being used to investigate the mechanisms by which lack of dystrophin results in weakness and to examine myoblast transfer as a treatment modality. A model of eosinophilia-myalgia syndrome has recently been induced in Lewis rats by the feeding of L-tryptophan samples that were implicated in the clinical syndrome in humans, making possible studies of the pathogenesis of this interesting new entity. A dermatomyositis-like syndrome occurs spontaneously in dogs, and polymyositis-like illnesses can be induced in mice by immunization with muscle or following infection with selected viruses, especially enteroviruses. Study of the latter is helping us understand mechanisms in the etiology and pathogenesis of inflammatory myositis and virus-induced autoimmunity.
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PMID:Animal models of myopathy. 177 47

A 30-year-old man showed exercise-induced myalgia, calf muscle hypertrophy and high serum creatine kinase level, without muscular weakness. The symptoms began in childhood and did not progress. Electromyographic findings were consistent with myopathy, and the muscle histology showed nonspecific myopathic changes without evidence of storage of glycogen or lipid. Immunohistochemical staining with antibodies raised against three different dystrophin peptides revealed proper subcellular localization of dystrophin at the sarcolemma of all myofibers, but the intensity of the stain was decreased. Western blot analysis using the same antibodies revealed normal dystrophin in size, but showed the reduced amount of the protein. The DNA obtained from the patient's peripheral leukocyte showed a deletion of the dystrophin gene including exon 45 by using PCR technique. Though the detailed size and portion of the deleted gene are not ascertained, the deletion in this case may not severely affect the function of dystrophin, unlike cases of Duchenne or Becker muscular dystrophy. Dystrophin analysis is useful for the etiologic diagnosis in cases of myalgia and high CKemia.
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PMID:[Exercise-induced myalgia and high CKemia with a deletion in the dystrophin gene]. 180 75

Becker muscular dystrophy (BMD) often results from in-frame mutations of the dystrophin gene that allow production of an altered but partially functional protein. To address potential structure-function relationships for the various domains of dystrophin, we examined both the dystrophin gene and protein in 68 patients with abnormal dystrophin. Eighty-six percent of BMD patients with dystrophin of altered size have deletions or duplications, and the observed sizes of dystrophin fit well with predictions based on DNA data. Deletions within the amino-terminal domain I tended to result in low levels of dystrophin and a more severe phenotype. The phenotypes of patients with deletions or duplications in the central rod domain were more variable. This region can be divided into three portions based on differences in clinical presentations of patients. Deletions around exons 4553 were most common and generally caused typical BMD; however, phenotypic variability among patients with similar mutations suggests that epigenetic and/or environmental factors play an important role in determining the clinical progression. In contrast, deletions or duplications in the proximal portion of this domain tended to cause severe cramps and myalgia. Finally, loss of the middle of this region probably causes a very mild phenotype, as only one such patient was found and his only symptom was elevated serum creatine phosphokinase levels.
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PMID:Exploring the molecular basis for variability among patients with Becker muscular dystrophy: dystrophin gene and protein studies. 206 77

We report a family with an X-linked recessive disorder characterized by muscle cramps and myalgia. Nine affected male family members had high resting serum levels of creatine kinase, and well-developed musculature with calf hypertrophy but no evidence of muscular weakness. Symptoms began in childhood and did not progress. Electromyographic findings were consistent with myopathy while muscle biopsies showed nonspecific myopathic changes without evidence of storage of glycogen or lipid. Analysis of DNA revealed a deletion in the 1st third of the dystrophin gene. Western blot analysis revealed that dystrophin was smaller than that in normal samples, with no reduction in the amount of the protein present. This disorder represents a new clinical phenotype associated with a deletion in the dystrophin gene. This deletion affects a portion of the dystrophin molecule that clinically does not appear to significantly alter its function. Other patients with deletions in this region may have truncated dystrophin without clinical signs of progressive muscle disease.
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PMID:Familial X-linked myalgia and cramps: a nonprogressive myopathy associated with a deletion in the dystrophin gene. 267 30

We report on a family with a severe form of X-linked dilated cardiomyopathy (DCM). Two brothers, the elder requiring heart transplantation, and a maternal cousin presented elevated creatine kinase levels, increased right ventricular diameters and electrocardiographic abnormalities. All complained of exertional cramping myalgia, but none had muscle weakness or a pathological electromyogram. Muscle biopsies of these individuals revealed a mild myopathic picture with atrophic type I and hypertrophic type II fibers. Immunofluorescence using N- and C-terminal antibodies (dys-2, dys-3) against the dystrophin protein showed preserved, but reduced intensity of staining of the sarcolemmal membranes. Using the same two antibodies, Western blot analyses revealed a dystrophin molecule of the expected molecular weight, which was quantitatively reduced by 80%. However, the dys-1 antibody, directed against the mid rod region of the dystrophin protein, did not react with dystrophin both on Western blot and immunofluorescence. Linkage analysis with polymorphic markers of the dystrophin gene revealed an identical haplotype at the 5' region in all affected individuals (two point lod score of 1.93, phi = 0). A deletion of exons 48, 45-53, 2-7 and 1 including the promoter region of the dystrophin gene, as described in rare cases with similar clinical signs could be excluded by multiplex PCR and Southern blot analyses of this DCM family. In addition, a major splice-mutation of dystrophin mRNA was excluded by RT-PCR of skeletal and heart muscle tissue. Therefore, we conclude that a novel mutation in the 5' region of the dystrophin gene phenotypically leads to this severe form of DCM. Extensive analyses of the dystrophin gene, in particular of the sequences coding for the antigenic determinants of the dys-1 antibody in the mid rod region, may identify the molecular cause of this monogenetic form of DCM.
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PMID:X-linked dilated cardiomyopathy. Novel mutation of the dystrophin gene. 775 93

A multidisciplinary study was conducted in order to assess dystrophin expression in a large series of mild X-linked muscular dystrophy patients, with well-defined clinical phenotype. Patients (104) were divided in 4 clinical groups, according to clinical severity: asymptomatic (sub-clinical), benign, moderate and severe, Cardiopathy was also assessed, and dilated cardiomyopathy was found in 47% of sub-clinical and benign cases. Myoglobinuria, cramps and myalgia were also associated with a sub-clinical or benign clinical status. Dystrophin immunohistochemical pattern of labelling and dystrophin amount decreased gradually across clinical groups. Our study showed a significative correlation between: (1) dystrophin amount and immunohistochemical score (p < 0.05); (2) dystrophin amount and clinical score (p < 0.05). Therefore, the combined use of these different techniques for prognosis of mild X-linked muscular dystrophy patients is useful. Our study assesses the prevalence of the various disease courses in a large cohort of mild X-linked muscular dystrophy patients. From our series, up to 30% of patients may be either asymptomatic or have sub-clinical changes.
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PMID:Clinical-molecular correlation in 104 mild X-linked muscular dystrophy patients: characterization of sub-clinical phenotypes. 798 92

We have investigated 59 Becker muscular dystrophy patients, representing 56 independent mutations, to test the hypothesis of predictability of muscle dystrophin expression and clinical phenotype based on location of dystrophin gene mutations. Partial intragenic deletions and duplications account for 82% of the independent mutations, of which 76.7% were deletions and 5.3% duplications. Mutations in which boundaries could be defined, were of in-frame type (35 out of 37, 94.6%, with two exceptions. Eighty-two percent of mutations were located at the distal part of the rod domain (exons 45-60), 9% at domain I (promoter through exon 9) and 9% at proximal and central parts of domain II. Domain I deleted patients tended to have a worse clinical phenotype, with earlier presentation, faster progression rate and lower dystrophin expression, while distal rod domain deleted patients showed a more classic Becker muscular dystrophy phenotype. Between these two groups, only the differences in the immunohistochemical patterns of dystrophin expression and disease progression rate were statistically significant. Partial clinical and biochemical heterogeneity was observed in the distal domain II patient group, due to the presence of few patients covering the extremities of clinical severity. Two asymptomatic patients had deletions located in the central (exons 41-44) and distal parts (exons 50-53) of the rod domain. Severe myalgia and cramps were often reported as early onset symptoms (18 out of 59): no correlation was found between this symptomatology and the location of the mutation. Relative levels of muscle dystrophin correlated with immunohistochemical patterns of subsarcolemma staining. Dystrophin levels (as estimated by 30 kDa antibody immuno-reactivity) correlated with age of reaching a moderate degree of muscle involvement as well as with delay in reaching that stage, a parameter of disease progression rate. Our data confirm that different Becker muscular dystrophy gene in-frame mutations have different effects on dystrophin expression and clinical severity, indicating several functional roles of the dystrophin domains.
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PMID:Clinical variability in Becker muscular dystrophy. Genetic, biochemical and immunohistochemical correlates. 814 4

We report here three related patients with a duplication of exons 19-41 of the dystrophin gene, having dissimilar clinical phenotype and dystrophin immunohistochemistry. Two brothers aged six and three years had myalgia, proximal muscular weakness and hypertrophic calves, with 10- 20-fold increase of serum creatine kinase. Muscle biopsy showed dystrophic changes and reduced, patchy binding of dystrophin. The clinical and laboratory findings were consistent with a diagnosis of Becker muscular dystrophy with early onset. Their 14-year-old cousin had only mild hyperCKemia. His muscle biopsy was normal with only mild reduction of dystrophin immunostaining. At follow-up, he is still without symptoms and signs at age 19. All three patients had the same gene duplication and an increased dystrophin size of 507 kDa. Expression of the dystrophin-associated glycoproteins adhalin, alpha-dystroglycan, and beta-dystroglycan were normal in the three patients. An intrafamilial variability in patients carrying a partial duplication of the dystrophin gene may be related to a quantitative difference in mRNA.
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PMID:Duplication of dystrophin gene and dissimilar clinical phenotype in the same family. 858 Jul 29

We report a Japanese Becker muscular dystrophy (BMD) patient with occasional myalgia and cramps during normal activity that developed at the age of 28 months. His family history was negative for neuromuscular diseases. Muscle biopsy analyses, including dystrophin immunostaining, disclosed no clinically relevant findings. The diagnosis of BMD was initially made at the age of 10 years, when indications of persistent high serum levels of CK prompted us to screen deletions in the dystrophin gene by amplification of 19 deletion-prone exons from the genomic DNA by the polymerase chain reaction (PCR). Among the exons examined, exons 13 and 17 were deleted. To clarify the size of the deletion, the dystrophin transcript was analyzed by reverse transcription PCR. The determined nucleotide sequence of the amplified product encompassing exons 10 to 20 disclosed that the entire segment corresponding to exons 13 to 18 (810 bp) was absent, a deletion that would be expected to cause the production of a dystrophin protein lacking 270 amino acids from the rod domain. This result indicates that occasional myalgia and cramps could be early clinical manifestations of mild BMD, especially in patients who have a deletion in the rod domain, and that deletion screening of the dystrophin gene might be the only reliable method to diagnose such cases.
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PMID:A Japanese boy with myalgia and cramps has a novel in-frame deletion of the dystrophin gene. 862 80


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