Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026850 (muscular dystrophy)
 5,870 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Episodes of acute myoglobinuria or cardiac arrest were occasionally complicated in general anesthesia of patients with Duchenne or Becker muscular dystrophy (DMD/BMD). Whether these complications are malignant hyperthermia (MH) or not has several times been discussed. In the present study, we applied the clinical grading scale (CGS) of Larach and modified criteria of caffeine contracture test of the skinned fiber (sIVCT) to solve this problem. When the CGS was applied to reported MH-like episodes of DMD/BMD cases, 9 out of 20 cases were classed as almost certain or very likely MH. According to results of sIVCT in 11 patients with DMD/BMD, 5 patients were judged as MHS (MH-susceptible) and 3 as MHE (MH-equivocal). The diagnostic specificity of present MHS criteria was 100% for the fulminant MH. A possible "false positive" result in European IVCT has been discussed in relation to myopathy such as muscular dystrophy. When we applied our sIVCT to the muscle of mdx mouse, caffeine contracture was rather reduced compared to controls. Present study suggested that a true MH was complicated in some cases of DMD/BMD. In certain stage of muscular degeneration, patients with DMD/BMD become susceptible to MH, probably temporarily, but exact mechanism still awaits clarification.
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PMID:[Malignant hyperthermia of Duchenne muscular dystrophy: application of clinical grading scale and caffeine contracture of skinned muscle fibers]. 1100 22

Previous investigators have suggested that proteolysis by calpain, a Ca2+-dependent protease, causes muscle fiber degradation in Duchenne and Becker muscular dystrophies (DMD/BMD). Recent evidence indicates that the nonlysosomal ATP-ubiquitin-dependent proteolytic complex (proteasomes) participates in muscle wasting during various catabolic states and in muscle fiber degradation in physiological or pathological conditions. To elucidate the possible role of proteasomes in dystrophic muscles, routine histochemistry and immunohistochemistry of 26S proteasomes were performed on muscle biopsy specimens obtained from patients with various neuromuscular disorders including DMD/BMD, polymyositis (PM), amyotrophic lateral sclerosis, and peripheral neuropathies, and on normal human muscle specimens. Immunohistochemically, proteasomes were located in the cytoplasm in normal human muscle, but their staining intensity was faint. Compared to control muscles, abnormal increases in both proteasomes and ubiquitin were demonstrated mainly in the cytoplasm of necrotic fibers and to a lesser extent in regenerative fibers in DMD/BMD and PM. Non-necrotic, atrophic fibers in all diseased muscles showed moderate or weak immunoreactions for the proteins; their staining intensities were stronger than those of control muscle fibers. Both proteins often colocalized well. Not all dystrophin-deficient muscle fibers showed a strong reaction for proteasomes. Our results showed increased proteasomes in necrotic and regenerative muscle fibers in DMD/ PMD, although this may not be disease-specific up-regulation. We suggest that the ATP-ubiquitin-dependent proteolytic pathway as well as the nonlysosomal calpain pathway may participate in muscle fiber degradation in muscular dystrophy.
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PMID:Proteasome expression in the skeletal muscles of patients with muscular dystrophy. 1107 10

The cardiac features of a novel form of congenital muscular dystrophy (Salih CMD) are described in two adolescent siblings. The patients presented with severe hypotonia at birth, associated with delayed development. They could walk independently and managed to maintain walking after 13 years of age. Their muscle immunohistochemistry differed from that seen in Duchenne and Becher muscular dystrophy (DMD and BMD), severe childhood autosomal recessive muscular dystrophy (SCARMD) due to sarcoglycan deficiency (sarcoglycanopathies), and lamininalpha2 (merosin)-deficient CMD. However, both patients had associated cardiomyopathy. Electrocardiography (ECG) in Salih CMD was characterized by delayed atrioventricular (AV) conduction, left anterior fascicular block (left axis deviation), and left atrial enlargement without evidence of atrial dysarrhythmia. Echocardiography showed features of severe left ventricular dysfunction with estimated left ventricle ejection fraction (LVEF) of 25% at 16 years-of-age in the older patient. A year later, multigated aquisition MUGA scan showed LVEF of 21% and dilatation of the right ventricle. Echocardiography and MUGA scan were normal in the younger patient at 15 years-of-age. ECG, echocardiography, and MUGA scan are effective techniques for diagnosing and monitoring the cardiomyopathy in Salih CMD. They can also distinguish it from features seen in the other common forms of MD, including DMD, BMD, and sarcoglycanopathies.
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PMID:Distinguishing cardiac features of a novel form of congenital muscular dystrophy (Salih cmd). 1145 96

Duchenne (DMD) and Becker (BMD) muscular dystrophies are an heterogeneous group of diseases characterized by a progressive muscular degeneration. The locus involved is localized on short arm of chromosome X (2.1) and the gene product has been called dystrophin. The total dystrophin deficiency leads to DMD while the reduction of dystrophin expression to BMD. The dystrophin has an elevated molecular weight (427 Kd) with different isoforms expressed in skeletal muscular system, central nervous system and myocardium tissue. The cardiovascular involvement is up to the muscular dystrophy: in the DMD patients it is secondary to the progressive course and it usually seen in wheel-chair patients. We have retrospectively evaluated through electrophysiology (EKG) and Echo (M-mode and 2 dimensional) studies 10 DMD patients to define the heart involvement.
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PMID:[Cardiologic study of 10 patients with Duchenne muscular dystrophy(DMD): personal experience]. 1148 24

Duchenne and Becker muscular dystrophies (D/BMD) are caused by mutations in the dystrophin gene. Two-thirds of patients have large intragenic deletions or duplications and the remaining one-third have point mutations, small deletions or insertions. Point mutations are more difficult to detect due to the enormous size (2.4 Mb) of the gene and its large transcript (14 kb). In the present study, a total of 50 DNA samples from unrelated D/BMD (38 DMD and 12 BMD) patients who did not show intragenic deletions by multiplex PCR, were analyzed for detection of point mutations. Single stranded conformation analysis and heteroduplex analysis observed electrophoretic mobility shifts in one (BMD) and two (DMD and BMD) patients, respectively. The mobility shift and heteroduplexes were observed in exon 17 in all of the three patients. Sequencing of the amplified PCR products revealed a nucleotide change (-37 g to t) in the intronic region in two of the patients while a C2268T substitution in the exonic region in one. Mutation database search for D/BMD mutations showed the nucleotide substitution in the exonic region as a novel change in the human dystrophin gene, which was not reported earlier. It resulted in an amino acid transition from threonine to methionine in the 687th position of the dystrophin protein. This novel substitution has been included in the mutation database of Leiden muscular dystrophy pages (http://www.dmd.nl) in the rare polymorphism/mutation category. The substituted nucleotide segregated with the disease phenotype in the family suggesting that it can be directly used for carrier detection and prenatal diagnosis without identification of disease causing mutation.
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PMID:Point mutation and polymorphism in Duchenne/Becker muscular dystrophy (D/BMD) patients. 1179 88

Complex diagnosis of muscular dystrophies including clinical, bioptical and molecular genetic approaches has been provided in a limited extent in this country. Our group of neurologists, pathologists and geneticists has examined approximately 240 patients suspected of having muscular dystrophies, mostly coming from Southern and Northern Moravia. The patients were sent to the examination most often from departments of neurology and clinical genetics, and less frequently from departments of internal medicine. According to the final diagnosis, the patients were divided into groups: with dystrophinopathies and carriers of dystrophinopathies (DMD/BMD), merosin deficient form of congenital muscular dystrophy, and Emery-Dreifuss muscular dystrophy including the carriers of this disease. Some relatives of patients with dystrophinopathies were also examined using the methods of segregation analysis. High proportion of the DMD/BMD patients can be detected by the methods of molecular genetics. Analysis of mRNA using RT PCR and PTT enables the detection of deletions, duplications, and point mutations in dystrophin gene and encompasses a larger diagnostic scope in comparison with examinations of DNA level by the multiplex PCR method from the peripheral blood which enables only deletion detections. Immunophenotyping of the dystrophin protein plays an important role especially using antibodies against carboxyterminal (DYS2) and rod domain (DYS1) of dystrophin. Deficient sarcolemmal expression of DYS2 and DYS1 reveals unambiguously a pathological dystrophin. On the other hand, less pronounced deficiencies in dystrophin expression in BMD patients and DMD/BMD carriers may not always be detected in muscle biopsies. In this case, it is necessary to supplement the examination by Western blotting and genotype analysis. The examination of patients with clinically diagnosed muscular dystrophy should start with a muscle biopsy which enables the estimation of presence and degree of structural changes. Application of antibodies against the components of DGC and emerin may reveal a deficiency in expression of these proteins. Immunohistochemical examination completed by Western blotting leads to the subsequent molecular genetic analysis of DNA or mRNA. Secondary deficiencies in expression of other DGC proteins are often revealed in muscle biopsies of dystrophinopathies and this fact must be taken into account in the evaluation of immunohistochemical findings. There is a possibility of replacement of invasive muscle biopsy by skin biopsy or buccal mucosal smears in cases of merosin and emerin deficiencies. Commercially available antibodies against merosin, emerin, calpain and sarcoglycans enable extensive identification and detailed classification of muscular dystrophies. Screening of the patients based on the application of methods described and discussed in this report is the task of the forthcoming period.
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PMID:[Muscular dystrophies detected by immunophenotyping and genotype analysis (mRNA and DNA)]. 1181 30

We report for the last 1 year and 9 months results of the molecular diagnosis of Duchenne (DMD) and Becker (BMD) muscular dystrophy at Kobe University. Analysis was done on 87 patients belonging to 76 families (66 DMD cases, 10 BMD cases). We first determined the presence of deletions or duplications using Southern blot analysis. Then analyzed small mutations (point mutations or small deletions/insertions) by mRNA analysis using RT-PCR and direct sequencing. 69 mutations (89.5%) were found, 46 deletions (60.5%), 5 duplications (6.6%) and 17 point mutations (22.4%) including 15 nonsense mutation. mRNA analysis from lymphocytes or muscle was useful for screening patients without a mutation identifiable by Southern blot analysis.
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PMID:[Dystrophin gene analysis on 76 families with dystrophinopathy]. 1223 50

In the course of a mutation search performed by muscle dystrophin transcript analysis in 72 Duchenne and Becker Muscular Dystrophies (DMD/BMD) patients without gross gene defect, we encountered four unrelated cases with additional out-of-frame sequences precisely intercalated between two intact exons of the mature muscle dystrophin mRNA. An in silico search of the whole dystrophin genomic sequence revealed that these inserts correspond to cryptic exons flanked by one strong and one weak consensus splice site and located in the mid-part of large introns (introns 60, 9, 1M, and 62, respectively). In each case we identified an intronic point mutation activating the cryptic donor or acceptor splice site. The patients exhibited a BMD/intermediate phenotype consistent with the presence of reduced amounts of normally spliced transcript and normal dystrophin. The frequency of this new type of mutation is not negligible (6% of our series of 65 patients with 'small' mutations). It would be missed if the exploration of the DMD gene is exclusively performed on exons and flanking sequences of genomic DNA.
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PMID:Dystrophinopathy caused by mid-intronic substitutions activating cryptic exons in the DMD gene. 1465 7

Analyses of deletions in the dystrophin gene and of cognitive status were performed on patients with Duchenne (DMD) or Becker (BMD) muscular dystrophy in order to find a correlation between both features. Molecular study by multiplex and simplex PCR of dystrophin exons led to the identification of 51 deletions in 126 unrelated patients. Most of them were frameshift, in full agreement with severe clinical symptoms, three patients with a BMD-like phenotype had in-frame mutations. Deletions were localized with reference to the different dystrophin isoform sequences and were clustered in two main areas, 5' and central+ 3' end of the gene. Cognitive abilities were tested in 47 out of 51 patients with identified mutations, 23 of them being mentally impaired. Comparison of molecular and neuropsychological features showed that deletions localized in central and 3' parts of the gene (18 out of 23) are preferentially associated with mental impairment. Fourteen of them were found in the regulatory and coding sequences for the three CNS specific carboxy terminal isoforms. Therefore, though mutations with variable locations may lead to cognitive impairment, our results show that deletions in the distal portion of the gene are basically related to mental retardation.
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PMID:Dystrophin deletions and cognitive impairment in Duchenne/Becker muscular dystrophy. 1497 63

Fukuyama-type congenital muscular dystrophy (FCMD) is characterized by congenital muscular dystrophy in combination with central nervous system (CNS) abnormalities. Differential diagnosis of FCMD from Duchenne and Becker muscular dystrophies (DMD/BMD) or other types of congenital muscular dystrophy is occasionally difficult, because of their phenotypic similarity. The gene (FCMD) responsible for FCMD at 9q31 was isolated in 1998. In Japan, most FCMD-bearing chromosomes (87%) have a 3-kb retrotransposal insertion into the 3'-untranslated region (UTR) of the gene that could be derived from a single ancestral founder. Nine non-founder mutations have been identified in Japanese FCMD patients. Severe phenotype was significantly more frequent in patients who were compound heterozygotes for a point mutation and the founder mutation, than in homozygotes for the founder mutation. We developed a PCR-based diagnostic method for a rapid detection of the retrotransposal insertion mutation. Using this system, we screened 18 FCMD patients, and found 16 homozygotes and two heterozygotes for the insertion. We also evaluated the carrier frequency in the normal Japanese population. Six of 676 persons were recognized as a heterozygous carrier. Furthermore, we found three homozygotes for the FCMD founder mutation among 97 patients who had been said to have probable DMD/BMD without any DMD mutations. On the other hand, there were no FCMD homozygotes but four heterozygous carriers among 335 patients with DMD mutations. The diagnostic method we developed will provide a rapid and reliable diagnosis of FCMD, which can bring important information in genetic counseling, such as the accurate mode of inheritance, recurrence risk and a life expectancy.
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PMID:A rapid diagnostic method for a retrotransposal insertional mutation into the FCMD gene in Japanese patients with Fukuyama congenital muscular dystrophy. 1510 18


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