Duchenne Muscular Dystrophy (duchenne + muscular_dystrophy)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


Duchenne Muscular Dystrophy, 3rd edn

EUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2004
K. A. Jellinger
No abstract is available for this article. [source]


Mutational spectrum of DMD mutations in dystrophinopathy patients: application of modern diagnostic techniques to a large cohort,

HUMAN MUTATION, Issue 12 2009
Kevin M. Flanigan
Abstract Mutations in the DMD gene, encoding the dystrophin protein, are responsible for the dystrophinopathies Duchenne Muscular Dystrophy (DMD), Becker Muscular Dystrophy (BMD), and X-linked Dilated Cardiomyopathy (XLDC). Mutation analysis has traditionally been challenging, due to the large gene size (79 exons over 2.2,Mb of genomic DNA). We report a very large aggregate data set comprised of DMD mutations detected in samples from patients enrolled in the United Dystrophinopathy Project, a multicenter research consortium, and in referral samples submitted for mutation analysis with a diagnosis of dystrophinopathy. We report 1,111 mutations in the DMD gene, including 891 mutations with associated phenotypes. These results encompass 506 point mutations (including 294 nonsense mutations) and significantly expand the number of mutations associated with the dystrophinopathies, highlighting the utility of modern diagnostic techniques. Our data supports the uniform hypermutability of CGA>TGA mutations, establishes the frequency of polymorphic muscle (Dp427m) protein isoforms and reveals unique genomic haplotypes associated with "private" mutations. We note that 60% of these patients would be predicted to benefit from skipping of a single DMD exon using antisense oligonucleotide therapy, and 62% would be predicted to benefit from an inclusive multiexonskipping approach directed toward exons 45 through 55. Hum Mutat 30:1657,1666, 2009. © 2009 Wiley-Liss, Inc. [source]


Muscle-derived stem cells: Implications for effective myoblast transfer therapy

IUBMB LIFE, Issue 11 2005
Tracey F. Lee-Pullen
Abstract Stem cells have been proposed as a wonder solution for tissue repair in many situations and have attracted much attention in the media for both their therapeutic potential and ethical implications. In addition to the excitement generated by embryonic stem cells, research has now identified a number of stem cells within adult tissues which pose much more realistic targets for therapeutic interventions. Myoblast transfer therapy (MTT) has long been viewed as a potential therapy for the debilitating muscle-wasting disorder Duchenne Muscular Dystrophy. This technique relies on the transplantation of committed muscle precursor cells directly into the muscle fibres but has had little success in clinical trials. The recent discovery of a population of cells within adult muscle with stem cell-like characteristics has interesting implications for the future of such putative cell transplantation therapies. This review focuses on the characterization and application of these potential muscle-derived stem cells (MDSC) to MTT. IUBMB Life, 57: 731-736, 2005 [source]


Noninvasive Ventilation During Gastrostomy Tube Placement in Patients with Severe Duchenne Muscular Dystrophy: Case Reports and Review of the Literature

PEDIATRIC PULMONOLOGY, Issue 2 2006
D.J. Birnkrant MD
Abstract Individuals with Duchenne muscular dystrophy may benefit from gastrostomy tube feeding due to progressive dysphagia and malnutrition. However, due to their severely impaired pulmonary function, these individuals are at risk of severe complications when they are sedated or undergo anesthesia for the procedure. We previously described a technique of noninvasive positive pressure ventilation to provide respiratory support during gastrostomy tube placement in such patients, but this technique had risks and limitations. In this case report, we examine two alternative techniques we used to provide respiratory support successfully to patients with severe muscular dystrophy and malnutrition who underwent percutaneous endoscopic gastrostomy tube placement. We then review the literature and discuss the potential benefits, risks, and limitations of the above techniques and of other options for gastrostomy placement in people with severe muscular dystrophy. Pediatr Pulmonol. © 2005 Wiley-Liss, Inc. [source]


Age Dependence of the Human Skeletal Muscle Stem Cell in Forming Muscle Tissue

ARTIFICIAL ORGANS, Issue 3 2006
Ralf Schäfer
Abstract:, Human skeletal muscle stem cells from healthy donors aged 2,82 years (n = 13) and from three children suffering from Duchenne Muscular Dystrophy (DMD) were implanted into soleus muscles of immunoincompetent mice and were also expanded in vitro until senescence. Growth of implanted cells was quantified by structural features and by the amount of human DNA present in a muscle. Proliferative capacity in vitro and in vivo was inversely related to age of the donor. In vitro, a decline of about two mean population doublings (MPDs) per 10 years of donor's age was observed. Muscle stem cells from DMD children were prematurely aged. In general, cell preparations with low or decreasing content in desmin-positive cells produced more MPDs than age-matched high-desmin preparations and upon implantation more human DNA and more nonmyogenic than myogenic tissue. Thus, a "Desmin Factor" was derived which predicts "quality" of the human muscle tissue growing in vivo. This factor may serve as a prognostic tool. [source]


Parents' perspectives on coping with Duchenne muscular dystrophy

CHILD: CARE, HEALTH AND DEVELOPMENT, Issue 4 2005
C. L. Webb
Abstract Background, The author, who has a grown son with Duchenne Muscular Dystrophy (DMD), has personally experienced a lack of available information for parents about coping with DMD. Therefore, as a longtime personal goal, she developed this study to address that lack of information. Methods, Fifteen semi-structured interviews were conducted with 23 parents (n = 7 with both parents; n = 1 with two sisters; n = 6 with mothers only; n = 1 with father only). The purpose of the interviews was to examine the strategies parents use to cope when their sons have DMD. The interviews were conducted in 12 states, taped and transcribed. Results, Grounded theory analysis of the interview data indicated the willingness of these parents to share information to empower others like themselves. Conclusions, Parents want to be heard and valued as experts on DMD by medical and other professionals who interact with their sons. In addition, they want to proactively participate in their sons' lives and to encourage other parents to do the same. [source]


Diagnosis and management of Duchenne muscular dystrophy

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 4 2010
PETER BAXTER
No abstract is available for this article. [source]


Visuospatial attention disturbance in Duchenne muscular dystrophy

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 2 2010
MARIA CLARA DRUMMOND SOARES DE MOURA
Aim, The cognitive deficits present in the Duchenne muscular dystrophy (DMD) are not yet well characterized. Attention, considered to be the brain mechanism responsible for the selection of sensory stimuli, could be disturbed in DMD, contributing, at least partially, to the observed global cognitive deficit. The aim of this study was to investigate attentional function in individuals with DMD. Method, Twenty-five males (mean age 12y; SD 2y 2mo) with DMD and 25 healthy males (mean age 12y; SD 2y) were tested in a visuospatial task (Posner computerized test). They were instructed to respond as quickly as possible to a lateralized visual target stimulus with the ipsilateral hand. Their attention was automatically orientated by a peripheral prime stimulus or, alternatively, voluntarily orientated by a central spatially informative cue. Results, The main result obtained was that the attentional effect (sum of the benefit and the cost of attention) did not differ between the two groups in the case of automatic attention (p=0.846) but was much larger for individuals with DMD than for comparison individuals in the case of voluntary attention (p<0.001). Interpretation, The large voluntary attentional effect exhibited by the participants with DMD seems similar to that of younger children, suggesting that the disease is associated with delayed maturation of voluntary attention mechanisms. [source]


Management of scoliosis in Duchenne muscular dystrophy: a large 10-year retrospective study

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 6 2006
M Kinali MD
Scoliosis affects 75 to 90% of patients with non-ambulant Duchenne muscular dystrophy (DMD). Spinal surgery is the treatment of choice but the indication varies among centres. Some offer surgery to all non-ambulant patients, irrespective of scoliosis severity. Early surgery has the advantage of targeting DMD when cardiorespiratory function is preserved, but not all patients develop scoliosis. We report our 10-year experience of scoliosis management in 123 patients with DMD who were at least 17 years old at the time of the study. Scoliosis was absent in 10%, and mild, non-progressive (at least 30°) in 13% of patients. Another 13% had moderate scoliosis (31,50°) and were managed conservatively. Surgery was considered in 57% (70/123) of patients with scoliosis greater than 50° and eventually performed in 35%. The remaining patients either refused surgery (9%) or were unfit because of cardiorespiratory compromise (13%). In a further 7%, scoliosis (greater than 50°), first noted after 14 years of age, was progressing slowly and surgery was not performed. At 17 years there was no difference in survival, respiratory impairment, or sitting comfort among patients managed conservatively or with surgery. One-third (44/123) of our patients were managed satisfactorily without receiving spinal surgery. We provide insight into the natural history of scoliosis in DMD that should help families and clinicians with decision-making when surgery is considered. [source]


Treatment of the heart in Duchenne muscular dystrophy

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 3 2006
Peter Baxter
No abstract is available for this article. [source]


Charcot-Marie-Tooth neuropathy type 1A combined with Duchenne muscular dystrophy

EUROPEAN JOURNAL OF NEUROLOGY, Issue 10 2007
P. Vondracek
We report a 24-year-old male with an unusual combination of two inherited neuromuscular disorders , Charcot-Marie-Tooth (CMT) disease type 1A and Duchenne muscular dystrophy (DMD). A phenotypic presentation of this patient included features of both these disorders. Nerve conduction studies revealed demyelinating peripheral neuropathy. Electromyography showed a profound myogenic pattern. The serum creatine kinase level was highly elevated. Muscle biopsy revealed a dystrophic picture with deficient dystrophin immunostaining. CMT1A duplication on chromosome 17p11.2 was found. The frame-shift mutation c.3609,3612delTAAAinsCTT (p.K1204LfsX11) was detected in the dystrophin gene by analysing mRNA isolated from the muscle tissue. The patient inherited both these mutations from his mother. The combination of CMT1A and DMD has not been reported as yet. [source]


Severe alterations of endothelial and glial cells in the blood-brain barrier of dystrophic mdx mice

GLIA, Issue 3 2003
Beatrice Nico
Abstract In this study, we investigated the involvement of the blood-brain barrier (BBB) in the brain of the dystrophin-deficient mdx mouse, an experimental model of Duchenne muscular dystrophy (DMD). To this purpose, we used two tight junction markers, the Zonula occludens (ZO-1) and claudin-1 proteins, and a glial marker, the aquaporin-4 (AQP4) protein, whose expression is correlated with BBB differentiation and integrity. Results showed that most of the brain microvessels in mdx mice were lined by altered endothelial cells that showed open tight junctions and were surrounded by swollen glial processes. Moreover, 18% of the perivascular glial endfeet contained electron-dense cellular debris and were enveloped by degenerating microvessels. Western blot showed a 60% reduction in the ZO-1 protein content in mdx mice and a similar reduction in AQP4 content compared with the control brain. ZO-1 immunocytochemistry and claudin-1 immunofluorescence in mdx mice revealed a diffuse staining of microvessels as compared with the control ones, which displayed a banded staining pattern. ZO-1 immunogold electron microscopy showed unlabeled tight junctions and the presence of gold particles scattered in the endothelial cytoplasm in the mdx mice, whereas ZO-1 gold particles were exclusively located at the endothelial tight junctions in the controls. Dual immunofluorescence staining of ,-actin and ZO-1 revealed colocalization of these proteins. As in ZO-1 staining, the pattern of immunolabeling with anti,,-actin antibody was diffuse in the mdx vessels and pointed or banded in the controls. ,-actin immunogold electron microscopy showed gold particles in the cytoplasms of endothelial cells and pericytes in the mdx mice, whereas ,-actin gold particles were revealed on the endothelial tight junctions and the cytoskeletal microfilaments of pericytes in the controls. Perivascular glial processes of the mdx mice appeared faintly stained by anti-AQP4 antibody, while in the controls a strong AQP4 labeling of glial processes was detected at light and electron microscope level. The vascular permeability of the mdx brain microvessels was investigated by means of the horseradish peroxidase (HRP). After HRP injection, extensive perivascular areas of marker escape were observed in mdx mice, whereas HRP was exclusively intravascularly localized in the controls. Inflammatory cells, CD4-, CD8-, CD20-, and CD68-positive cells, were not revealed in the perivascular stroma of the mdx brain. These findings indicate that dystrophin deficiency in the mdx brain leads to severe injury of the endothelial and glial cells with disturbance in ,-actin cytoskeleton, ZO-1, claudin-1, and AQP4 assembly, as well as BBB breakdown. The BBB alterations suggest that changes in vascular permeability are involved in the pathogenesis of the neurological dysfunction associated with DMD. GLIA 42:235,251, 2003. © 2003 Wiley-Liss, Inc. [source]


The Golden Freeway: a preliminary evaluation of a pilot study advancing information technology as a social intervention for boys with Duchenne muscular dystrophy and their families

HEALTH & SOCIAL CARE IN THE COMMUNITY, Issue 1 2004
Jennifer Soutter BSc PhD
Abstract Established information technology was used in an attempt to reduce social isolation by providing each family who had a child with Duchenne muscular dystrophy with a personal computer, and e-mail and Internet connectivity. Seventy-four of the 88 families in the north of England (i.e. Cumbria, Durham, Northumberland, Teesside, and Tyne and Wear) with a boy with Duchenne muscular dystrophy who was diagnosed before January 2000 had the equipment installed. Evaluations of equipment usage and parental perceptions of the project were carried out at 3 and 12 months post-installation. Results from quantitative and qualitative interviews with parents indicated that benefits accrued to the families and to the boys themselves: family relationships can be extended, and the boys can acquire a degree of independence which, according to parents' views, can boost self-confidence and self-esteem. As hoped, social isolation was felt to have been reduced, and an occupation, interest and enjoyment provided. The greatest use of the computer was for schoolwork with siblings sharing in this. Cost proved to be a problem for a number of families. For the project team, there were unexpected aspects: creating an e-community was more difficult than anticipated, more training was required and not all families would ever use the equipment to its fullest. However, families did emphasise the value of the project as a way of opening the world for their sons. [source]


DMD exon 1 truncating point mutations: Amelioration of phenotype by alternative translation initiation in exon 6,

HUMAN MUTATION, Issue 4 2009
Olga L. Gurvich
Abstract Mutations in the DMD gene result in two common phenotypes associated with progressive muscle weakness: the more severe Duchenne muscular dystrophy (DMD) and the milder Becker muscular dystrophy (BMD). We have previously identified a nonsense mutation (c.9G>A; p.Trp3X) within the first exon of the DMD gene, encoding the unique N-terminus of the 427-kDa muscle isoform of the dystrophin protein. Although this mutation would be expected to result in severe disease, the clinical phenotype is very mild BMD, with ambulation preserved into the seventh decade. We identify the molecular mechanism responsible for the amelioration of disease severity to be initiation of translation at two proximate AUG codons within exon 6. Analysis of large mutational data sets suggests that this may be a general mechanism of phenotypic rescue for point mutations within at least the first two exons of the DMD gene. Our results directly demonstrate, for the first time, the use of alternate translational initiation codons within the DMD gene, and suggest that dystrophin protein lacking amino acids encoded by the first five exons retains significant function. Hum Mutat 0:1,8, 2009. © 2009 Wiley-Liss, Inc. [source]


Array-MLPA: comprehensive detection of deletions and duplications and its application to DMD patients,

HUMAN MUTATION, Issue 1 2008
Fanyi Zeng
Abstract Multiplex ligation-dependent probe amplification (MLPA) is widely used to screen genes of interest for deletions and duplications. Since MLPA is usually based on size-separation of the amplification products, the maximum number of target sequences that can be screened in parallel is usually limited to ,40. We report the design of a robust array-based MLPA format that uses amplification products of essentially uniform size (100,120,bp) and distinguishes between them by virtue of incorporated tag sequences. We were thus able to increase probe complexity to 124, with very uniform product yields and signals that have a low coefficient of variance. The assay designed was used to screen the largest set studied so far (249 patients) of unrelated Duchenne muscular dystrophy (DMD) cases from the Chinese population. In a blind study we correctly assigned 98% of the genotypes and detected rearrangements in 181 cases (73%); i.e., 163 deletions (65%), 13 duplications (5%), and five complex rearrangements (2%). Although this value is significantly higher for Chinese patients than previously reported, it is similar to that found for other populations. The location of the rearrangements (76% in the major deletion hotspot) is also in agreement with other findings. The 96-well flow-through microarray system used in this research provides high-throughput and speed; hybridization can be completed in 5 to 30,minutes. Since array processing and data analysis are fully automated, array-MLPA should be easy to implement in a standard diagnostic laboratory. The universal array can be used to analyze any tag-modified MLPA probe set. Hum Mutat 29(1), 190,197, 2008. © 2007 Wiley-Liss, Inc. [source]


Protein- and mRNA-based phenotype,genotype correlations in DMD/BMD with point mutations and molecular basis for BMD with nonsense and frameshift mutations in the DMD gene,

HUMAN MUTATION, Issue 2 2007
Nathalie Deburgrave
Abstract Straightforward detectable Duchenne muscular dystrophy (DMD) gene rearrangements, such as deletions or duplications involving an entire exon or more, are involved in about 70% of dystrophinopathies. In the remaining 30% a variety of point mutations or "small" mutations are suspected. Due to their diversity and to the large size and complexity of the DMD gene, these point mutations are difficult to detect. To overcome this diagnostic issue, we developed and optimized a routine muscle biopsy,based diagnostic strategy. The mutation detection rate is almost as high as 100% and mutations were identified in all patients for whom the diagnosis of DMD and Becker muscular dystrophy (BMD) was clinically suspected and further supported by the detection on Western blot of quantitative and/or qualitative dystrophin protein abnormalities. Here we report a total of 124 small mutations including 11 nonsense and frameshift mutations detected in BMD patients. In addition to a comprehensive assessment of muscular phenotypes that takes into account consequences of mutations on the expression of the dystrophin mRNA and protein, we provide and discuss genomic, mRNA, and protein data that pinpoint molecular mechanisms underlying BMD phenotypes associated with nonsense and frameshift mutations. Hum Mutat 28(2), 183,195, 2007. © 2006 Wiley-Liss, Inc. [source]


Multiexon skipping leading to an artificial DMD protein lacking amino acids from exons 45 through 55 could rescue up to 63% of patients with Duchenne muscular dystrophy,

HUMAN MUTATION, Issue 2 2007
Christophe Béroud
Abstract Approximately two-thirds of Duchenne muscular dystrophy (DMD) patients show intragenic deletions ranging from one to several exons of the DMD gene and leading to a premature stop codon. Other deletions that maintain the translational reading frame of the gene result in the milder Becker muscular dystrophy (BMD) form of the disease. Thus the opportunity to transform a DMD phenotype into a BMD phenotype appeared as a new treatment strategy with the development of antisense oligonucleotides technology, which is able to induce an exon skipping at the pre-mRNA level in order to restore an open reading frame. Because the DMD gene contains 79 exons, thousands of potential transcripts could be produced by exon skipping and should be investigated. The conventional approach considers skipping of a single exon. Here we report the comparison of single- and multiple-exon skipping strategies based on bioinformatic analysis. By using the Universal Mutation Database (UMD)-DMD, we predict that an optimal multiexon skipping leading to the del45-55 artificial dystrophin (c.6439_8217del) could transform the DMD phenotype into the asymptomatic or mild BMD phenotype. This multiple-exon skipping could theoretically rescue up to 63% of DMD patients with a deletion, while the optimal monoskipping of exon 51 would rescue only 16% of patients. Hum Mutat 28(2), 196,202, 2007. © 2006 Wiley-Liss, Inc. [source]


Resolution of skeletal muscle inflammation in mdx dystrophic mouse is accompanied by increased immunoglobulin and interferon-, production

INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 3 2002
Jussara Lagrota-Candido
Summary. Mdx mouse, the animal model of Duchenne muscular dystrophy, develops an X-linked recessive inflammatory myopathy with an apparent sustained capacity for muscle regeneration. We analysed whether changes in the skeletal muscle during myonecrosis and regeneration would correlate with functional alterations in peripheral lymphoid tissues. Here we show that during the height of myonecrosis, mdx mice display marked atrophy of peripheral lymph nodes and extensive muscle inflammation. In contrast, enlargement of draining lymph nodes with accumulation of CD4+ CD44+, CD4+ CD25+, CD8+ CD44+ T lymphocytes and type-2 B cells was consistently observed during amelioration of the muscle lesion. In addition, regeneration of the muscular tissue was accompanied by concomitant increase of immunoglobulin-secreting cells in regional lymph nodes and bone marrow. Double immunolabelling analysis revealed intense B cell proliferation and formation of germinal centre in the follicles of dystrophic regional lymph nodes. Furthermore, lymph node cells produced large amounts of IFN-, but not IL-4, IL-6 or IL-10 after in vitro mitogen stimulation with Concanavalin A. As these alterations occurred mainly during the recovery period, we suggested that local activation of the immune system could be an influence which mitigates the myonecrosis of muscular tissue in the mdx dystrophic mouse. [source]


A review of nutrition in Duchenne muscular dystrophy

JOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 5 2009
Z. E. Davidson
Abstract Duchenne muscular dystrophy (DMD) is a recessive X linked genetic disorder characterised by progressive muscle weakness and reduced muscle tone. Affecting only boys, it limits life expectancy to approximately 20 years. A literature review was conducted using MEDLINE and the Cochrane Library, employing the term ,Duchenne muscular dystrophy'. A total of 1491 articles in English were recovered. These papers were searched thematically under the headings: body composition (n = 10), energy expenditure (n = 10), nutrition (n = 6), corticosteroid therapy (n = 55) and gene therapy (n = 199). Key dietetic practice points were identified relevant to nutritional management. Papers supporting these key themes were assigned a level of evidence and grade of recommendation. There is limited high-quality evidence to guide the nutritional management of boys with DMD. Currently, the majority of evidence is based on expert opinion and clinical expertise. Delayed growth, short stature, muscle wasting and increased fat mass are characteristics of DMD and impact on nutritional status and energy requirements. The early introduction of steroids has altered the natural history of the disease, but can exacerbate weight gain in a population already susceptible to obesity. Prior to commencing steroids, anticipatory guidance for weight management should be provided. Malnutrition is a feature of end stage disease requiring a multidisciplinary approach, such as texture modification and supplemental feeding. Micronutrient requirements are yet to be determined but, as a result of corticosteroid treatment, vitamin D and calcium should be supplemented. Some evidence exists supporting supplementation with creatine monohydrate to improve muscle strength. More research is needed to provide a higher quality of evidence for dietitians working within this area. [source]


The 6-minute walk test as a new outcome measure in Duchenne muscular dystrophy

MUSCLE AND NERVE, Issue 4 2010
Craig M. McDonald MD
Abstract Walking abnormalities are prominent in Duchenne muscular dystrophy (DMD). We modified the 6-minute walk test (6MWT) for use as an outcome measure in patients with DMD and evaluated its performance in 21 ambulatory boys with DMD and 34 healthy boys, ages 4 to 12 years. Boys with DMD were tested twice, ,1 week apart; controls were tested once. The groups had similar age, height, and weight. All tests were completed. Boys who fell recovered rapidly from falls without injury. Mean ± SD [range] 6-minute walk distance (6MWD) was lower in boys with DMD than in controls (366 ± 83 [125,481] m vs. 621 ± 68 [479,754] m; P < 0.0001; unpaired t -test). Test-retest correlation for boys with DMD was high (r = 0.91). Stride length (R2 = 0.89; P < 0.0001) was the major determinant of 6MWD for both boys with DMD and controls. A modified 6MWT is feasible and safe, documents disease-related limitations on ambulation, is reproducible, and offers a new outcome measure for DMD natural history and therapeutic trials. Muscle Nerve, 2010 [source]


Assessment of regional body composition with dual-energy X-ray absorptiometry in Duchenne muscular dystrophy: Correlation of regional lean mass and quantitative strength

MUSCLE AND NERVE, Issue 5 2009
Andrew J. Skalsky MD
Abstract The purpose of this study was to assess regional body composition and its correlation with regional strength in Duchenne muscular dystrophy (DMD) subjects and able-bodied controls. Regional dual-energy X-ray absorptiometry (DEXA) measurements and isometric strength were obtained for 23 DMD subjects and 23 control subjects. DMD subjects showed a decreased regional lean mass (P < 0.001). The correlation between regional strength and regional lean mass was stronger for controls than for DMD subjects. DMD subjects had decreased regional lean mass, increased regional fat mass, and decreased strength. Muscle Nerve 39: 647,651, 2009 [source]


Muscle ultrasound in neuromuscular disorders

MUSCLE AND NERVE, Issue 6 2008
Sigrid Pillen MD
Abstract Muscle ultrasound is a useful tool in the diagnosis of neuromuscular disorders, as these disorders result in muscle atrophy and intramuscular fibrosis and fatty infiltration, which can be visualized with ultrasound. Several prospective studies have reported high sensitivities and specificities in the detection of neuromuscular disorders. Although not investigated in large series of patients, different neuromuscular disorders tend to show specific changes on muscle ultrasound, which can be helpful in differential diagnosis. For example, Duchenne muscular dystrophy results in a severe, homogeneous increase of muscle echo intensity with normal muscle thickness, whereas spinal muscular atrophy shows an inhomogeneous increase of echo intensity with severe atrophy. A major advantage of muscle ultrasound, compared to other imaging techniques, is its ability to visualize muscle movements, such as muscle contractions and fasciculations. This study reviews the possibilities and limitations of ultrasound in muscle imaging and its value as a diagnostic tool in neuromuscular disorders. Muscle Nerve, 2008 [source]


Cognitive impairment in neuromuscular disorders

MUSCLE AND NERVE, Issue 1 2006
Maria Grazia D'Angelo MD
Abstract Several studies have suggested the presence of central nervous system involvement manifesting as cognitive impairment in diseases traditionally confined to the peripheral nervous system. The aim of this review is to highlight the character of clinical, genetic, neurofunctional, cognitive, and psychiatric deficits in neuromuscular disorders. A high correlation between cognitive features and cerebral protein expression or function is evident in Duchenne muscular dystrophy, myotonic dystrophy (Steinert disease), and mitochondrial encephalomyopathies; direct correlation between tissue-specific protein expression and cognitive deficits is still elusive in certain neuromuscular disorders presenting with or without a cerebral abnormality, such as congenital muscular dystrophies, congenital myopathies, amyotrophic lateral sclerosis, adult polyglucosan body disease, and limb-girdle muscular dystrophies. No clear cognitive deficits have been found in spinal muscular atrophy and facioscapulohumeral dystrophy. Muscle Nerve, 2006 [source]


Annexin expression in inflammatory myopathies

MUSCLE AND NERVE, Issue 1 2004
Stefan Probst-Cousin MD
Abstract The pathogenesis of the inflammatory myopathies is still unclear, making their treatment largely empirical. Improved understanding of the molecular mechanisms of inflammatory muscle injury may, however, lead to the development of more specific immunotherapies. To elucidate a possible pathogenic contribution of calcium-binding proteins such as the annexins, we immunohistochemically investigated muscle biopsy specimens from patients with dermatomyositis (10 cases), polymyositis (9 cases), and inclusion-body myositis (4 cases), compared to control cases comprising sarcoid myopathy (3 cases), Duchenne muscular dystrophy (DMD; 4 cases), and normal muscle (3 cases). We found expression of annexins A1, A2, A4, and A6 in the vascular endothelium of all cases. Myofibers expressed annexins A5, A6, and A7 diffusely and weakly in the cytosol, whereas annexins A5 and A7 were also particularly localized to the sarcolemma. In the inflammatory myopathies, in areas of myonecrosis in DMD, and in granulomatous lesions of sarcoid myopathy, reactivity of annexins A1, A2, A4, A5, and A6 was observed in macrophages and T-lymphocytes. Whereas the latter annexins appear to be nonspecific indicators of activation, annexin A1 upregulation may represent endogenous anti-inflammatory mechanisms that merit further investigation. Muscle Nerve 30: 102,110, 2004 [source]


Gentamicin fails to increase dystrophin expression in dystrophin-deficient muscle

MUSCLE AND NERVE, Issue 5 2003
Patrick Dunant PhD
Abstract A recent report that aminoglycoside antibiotics restored the expression of functional dystrophin to skeletal muscles of mdx mice, a model of Duchenne muscular dystrophy (DMD), raised hopes that DMD may be treatable by a conventional drug. Subsequently, several human trials were initiated for evaluating gentamicin therapy in selected DMD patients. An increase of dystrophin expression was not detected in one human trial that was fully reported. Here, we report that we were unable to replicate previously published beneficial results by gentamicin treatment in the mdx mouse. Therefore, we believe that additional animal experimentation is required to further evaluate the possibility of in vivo aminoglycoside therapy of DMD. Muscle Nerve 27: 624,627, 2003 [source]


Immunohistological intensity measurements as a tool to assess sarcolemma-associated protein expression

NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 4 2010
V. Arechavala-Gomeza
V. Arechavala-Gomeza, M. Kinali, L. Feng, S. C. Brown, C. Sewry, J. E. Morgan and F. Muntoni (2010) Neuropathology and Applied Neurobiology36, 265,274 Immunohistological intensity measurements as a tool to assess sarcolemma-associated protein expression Aims: The quantification of protein levels in muscle biopsies is of particular relevance in the diagnostic process of neuromuscular diseases, but is difficult to assess in cases of partial protein deficiency, particularly when information on protein localization is required. The combination of immunohistochemistry and Western blotting is often used in these cases, but is not always possible if the sample is scarce. We therefore sought to develop a method to quantify relative levels of sarcolemma-associated proteins using digitally captured images of immunolabelled sections of skeletal muscle. Methods: To validate our relative quantification method, we labelled dystrophin and other sarcolemmal proteins in transverse sections of muscle biopsies taken from Duchenne muscular dystrophy and Becker muscular dystrophy patients, a manifesting carrier of Duchenne muscular dystrophy and normal controls. Results: Using this method to quantify relative sarcolemmal protein abundance, we were able to accurately distinguish between the different patients on the basis of the relative amount of dystrophin present. Conclusions: This comparative method adds value to techniques that are already part of the diagnostic process and can be used with minimal variation of the standardized protocols, without using extra amounts of valuable biopsy samples. Comparative quantification of sarcolemmal proteins on immunostained muscle sections will be of use to establish both the abundance and localization of the protein. Moreover, it can be applied to assess the efficacy of experimental therapies where only partial restoration or upregulation of the protein may occur. [source]


Reversal of rocuronium-induced neuromuscular blockade by pyridostigmine in patients with Duchenne muscular dystrophy

PEDIATRIC ANESTHESIA, Issue 3 2008
TINO MUENSTER MD
Summary Background:, The aim of this study was to investigate the effect and safety of pyridostigmine for the reversal of a neuromuscular block (NMB) in patients with Duchenne muscular dystrophy (DMD). In patients with DMD recovery from a rocuronium-induced NMB is markedly delayed. Methods:, Fourteen DMD patients (aged between 11 and 19 years) scheduled for elective scoliosis repair were studied. Following tracheal intubation without muscle relaxant, all patients received a single dose of rocuronium 0.6 mg·kg,1. NMB was monitored by acceleromyography at the adductor pollicis muscle. When the first twitch height (T1) of the train-of-four (TOF) had recovered to 25% seven patients received either pyridostigmine 0.1 mg·kg,1 (the anticholinergic drug with a long duration of action) or saline in a blinded manner. The times to attain TOF ratio of 0.9 were recorded. For comparison the Mann,Whitney U -test was used. Results:, Recovery to TOF ratio of 0.9 was significantly (P < 0.05) accelerated by pyridostigmine [84 (median), 57,141(range)] compared with controls (148, 84,243 min). The recovery time (time between T1 of 25% and TOF of 90%) was also significantly (P < 0.01) shortened by pyridostigmine (15, 8,49 vs 76, 43,144 min, respectively). Time to recovery of T1 to 90% was not different between the groups (108, 63,134 vs 169. 61,208 min, respectively). Conclusions:, Pyridostigmine 0.1 mg·kg,1 effectively reversed a rocuronium-induced NMB in DMD patients. [source]


C Histomorphology of neuromuscular junction in Duchenne muscular dystrophy

PEDIATRIC ANESTHESIA, Issue 3 2008
MARY C THEROUX MD
Summary Background:, Our objective was to better understand neuromuscular junction (NMJ) morphology in children with Duchenne muscular dystrophy (DMD). Methods:, We examined the NMJs of four children, age 6,13 years, who were diagnosed with DMD. Using our previously established staining technique, we examined the gross appearance of the NMJs in patients with DMD and evaluated the spread of acetylcholine receptors (AChRs) in relationship to the NMJs. We used a computerized algorithm to measure the area of staining corresponding to AChRs and NMJ. Results:, Abnormal shape and morphological appearance of some of the NMJs was clearly evident. The spread of AChRs in DMD patients is comparable with the spread of AChRs in nonDMD patients. Conclusions:, The distribution of AChRs in relationship to the boundaries of NMJs in DMD children is similar to the distribution of NMJs in the erector spinae muscles of idiopathic scoliosis patients. [source]


The respiratory management of patients with duchenne muscular dystrophy: A DMD care considerations working group specialty article,

PEDIATRIC PULMONOLOGY, Issue 8 2010
David J. Birnkrant MD
Abstract In 2001, the Muscular Dystrophy Community Assistance, Research and Education Amendments (MD-CARE Act) was enacted, which directed federal agencies to coordinate the development of treatments and cures for muscular dystrophy. As part of the mandate, the Centers for Disease Control and Prevention (CDC) initiated surveillance and educational activities, which included supporting development of care considerations for Duchenne muscular dystrophy (DMD) utilizing the RAND/UCLA Appropriateness Method (RAM). This document represents the consensus recommendations of the project's 10-member Respiratory Panel and includes advice on necessary equipment, procedures and diagnostics; and a structured approach to the assessment and management of the respiratory complications of DMD via assessment of symptoms of hypoventilation and identification of specific thresholds of forced vital capacity, peak cough flow and maximum expiratory pressure. The document includes a set of Figures adaptable as "pocket guides" to aid clinicians. This article is an expansion of the respiratory component of the multi-specialty article originally appearing in Lancet Neurology, comprising respiratory recommendations from the CDC Care Considerations project. Pediatr. Pulmonol. 2010; 45:739,748. © 2010 Wiley-Liss, Inc. [source]


New challenges in the management of prolonged survivors of pediatric neuromuscular diseases: A pulmonologist's perspective

PEDIATRIC PULMONOLOGY, Issue 12 2006
David J. Birnkrant MD
Abstract Many patients with pediatric neuromuscular diseases (NMDs) are now achieving prolonged survival through advances in management of the cardiopulmonary complications of their illnesses. Because respiratory complications are among the main causes of mortality and morbidity in these diseases, pulmonologists are in a unique position to observe and describe the largely unanticipated medical, social, and ethical problems generated when patients with progressive NMDs achieve prolonged survival. For example, prolonged survivors of pediatric NMDs are now experiencing previously rare or unknown medical complications, an unprecedented severity of burden of disease and the potential for prolonged impairment of quality of life. As the patients age, their families must cope with a high level of burden of care. Society's acceptance of the eligibility of these patients to utilize critical care resources, and issues related to the transition of prolonged survivors from pediatric to adult medical providers and venues have resulted in complex practical and ethical issues. In this article, the author, a pediatric pulmonologist closely involved in the care of patients with NMDs, will identify and discuss some of the major medical, social, and ethical implications of prolonged survival among these patients, with an emphasis on Duchenne muscular dystrophy (DMD), the most common of the pediatric NMDs. Pediatr Pulmonol. 2006; 41:1113,1117. © 2006 Wiley-Liss, Inc. [source]