Limb girdle muscular dystrophy: a pathological and immunohistochemical reevaluation

We investigated the involvement of IL-8 in the delayed vascular permeability (VP) in rabbit lipopolysaccharide (LPS)-pleurisy. Maximal level of interleukin-8 (IL-8) was detected in pleural fluid at 2 h after LPS injection and anti-IL-8 inhibited the delayed VP by 90%. Injection of homologous IL-8 induced VP, the time-course of which preceded that of LPS-induced delayed VP. Production of IL-8 in LPS-pleurisy was inhibited with anti-tumor necrosis factor alpha (TNF-alpha), whereas the production of TNF-alpha was not affected with anti-IL-8. Injection of IL-8 did not induce TNF-alpha production and anti-TNF-alpha had no effect on IL-8-induced VP. Injection of homologous TNF-alpha induced IL-8 production and VP, and TNF-alpha-induced delayed VP was blocked with anti-IL-8. These results indicate important roles of IL-8 in LPS-induced delayed VP and that TNF-alpha causes the delayed VP through the production of IL-8.     

Cardiomyopathy of limb-girdle muscular dystrophy

OBJECTIVES: This study sought to find an association between dilated cardiomyopathy and limb-girdle muscular dystrophy. BACKGROUND: Cardiomyopathy has been seen in various neuromuscular disorders, but it has not been recognized to be associated with limb-girdle muscular dystrophy. METHODS: We investigated three sisters with well documented limb-girdle dystrophy and congestive heart failure by the 3rd decade of life. All underwent noninvasive evaluation of left ventricular systolic function by both echocardiography and radionuclide scanning, and one also had cardiac catheterization. Deoxyribonucleic acid (DNA) linkage analysis was performed in these affected subjects and in the unaffected family members, and DNA was extracted from mononuclear cells with primer sequences for three chromosome 13q microsatellite markers. RESULTS: The parents had no evidence of clinical disease, but all three sisters had echocardiographic evidence of dilated cardiomyopathy. The sister with additional evidence of left ventricular dysfunction of cardiac catheterization had no coronary artery disease. The affected subjects had the same paternal allele for three potential markers of limb-girdle muscular dystrophy but different maternal alleles. The very small family size did not permit statistical confirmation or refutation of linkage for chromosome 13q markers. CONCLUSIONS: Demonstrable cardiomyopathy accompanying limb-girdle muscular dystrophy and its probable genetic associations require continued investigation by anticipating the cardiomyopathy in limb-girdle muscular dystrophy.     

Point mutation in a Becker muscular dystrophy patient

Occupational therapy intervention in the area of seating and positioning may play a vital role in improving the quality of life for nursing home residents. This case report indicates that appropriately positioning a client may increase comfort, decrease agitation, and decrease the administration of mood-altering drugs. Research would help to delineate the effects of appropriate seating systems, both to ensure reimbursement and to ensure that all who might benefit from positioning intervention receive the appropriate services. OBRA 1987 regulations are forcing nursing homes to assess residents for the least restrictive restraints. These assessments offer a golden opportunity for occupational therapists to become involved in determining the most appropriate seating systems and to conduct research on their benefits.     

Intestinal pseudoobstruction as a feature of myotonic muscular dystrophy

We report two cases of intestinal pseudoobstruction caused by visceral smooth muscle involvement due to myotonic muscular dystrophy. Two patients with myotonic muscular dystrophy presented with abdominal pain, distention, constipation, and vomiting. The exclusion of mechanical obstruction by plain abdominal radiography, contrast studies, and colonoscopy led to the diagnosis of intestinal pseudoobstruction. Diagnosis was confirmed by manometric and cineradiographic findings of abnormal intestinal motility. Conservative management including laxatives and cisapride led to the resolution of the pseudoobstruction syndrome and long-term remission without relapses during a two year follow-up. In patients with known myotonic dystrophy the occurrence of intestinal pseudoobstruction should be considered in order to avoid unnecessary laparotomies.     

Microsatellite analysis of Duchenne muscular dystrophy

Duchenne muscular dystrophy is X-linked recessive neuromuscular disorders caused by mutations in the dystrophin gene. Prenatal diagnosis and carrier detection are usually performed using diallelic RFLP-markers which are not always informative. Now 30 of microsatellite marker have reported, these microsatellite polymorphism can easily be amplified using PCR technique. If mutations are known to localize in this region of the dystrophin gene or if routine RFLP-analysis is uninformative, the analysis of microsatellite markers is the preferable technique in prenatal diagnosis and carrier detection.     

Utrophin-dystrophin-deficient mice as a model for Duchenne muscular dystrophy

The absence of dystrophin at the muscle membrane leads to Duchenne muscular dystrophy (DMD), a severe muscle-wasting disease that is inevitably fatal in early adulthood. In contrast, dystrophin-deficient mdx mice appear physically normal despite their underlying muscle pathology. We describe mice deficient for both dystrophin and the dystrophin-related protein utrophin. These mice show many signs typical of DMD in humans: they show severe progressive muscular dystrophy that results in premature death, they have ultrastructural neuromuscular and myotendinous junction abnormalities, and they aberrantly coexpress myosin heavy chain isoforms within a fiber. The data suggest that utrophin and dystrophin have complementing roles in normal functional or developmental pathways in muscle. Detailed study of these mice should provide novel insights into the pathogenesis of DMD and provide an improved model for rapid evaluation of gene therapy strategies.     

Sensorineural hearing loss in the mdx mouse: a model of Duchenne muscular dystrophy

Sensorineural hearing loss has been identified in several types of muscular dystrophy, but few studies have investigated any relationship between Duchenne muscular dystrophy and hearing. An animal model of Duchenne muscular dystrophy, the mdx mouse, exhibits the same genetic defect as humans. We performed brainstem auditory evoked responses on mdx and control mice in order to assess sensorineural hearing loss. The amplitude and latency of wave I for each animal were measured at increasing sound pressure levels. A significant increase in threshold and a decrease in wave I amplitude were found in the mdx mice. These results indicate that significant sensorineural hearing loss is associated with muscular dystrophy in the mdx mouse. Possible cellular mechanisms contributing to the hearing deficit are presented.     

Steroids in muscular dystrophy: where do we stand?

Sorption of essential oil aroma components, n-alcohols and linalool by starch corn cryotexture was studied. Results show that terpene hydrocarbons of Rosmarinus officinalis L. essential oil are sorbed quantitatively from 0.05% water solution by cryotexture due to hydrophobic interactions with starch polysaccharides. Aroma compounds with oxygen atoms within the molecule are sorbed two times less. A templating effect with glucose, sucrose, maltose and some essential oil components was observed. Sorption of n-alcohols C4, C6, C8, linalool and their mixture with alkyl acetates in concentration 0.5-15 mmol/l was carried out. Individual octanol is sorbed by cryotexture on 88%, hexanol on 20%, linalool on 25%. Butanol is not sorbed at the chosen concentration. Synergism in sorption of hexanol from mixture with octanol and alkyl acetates was observed, while a suppression effect of octanol sorption was found for the same mixture.     

Intellectual functioning in Duchenne muscular dystrophy: A review.

Duchenne muscular dystrophy has traditionally been thought to be a primary disease of muscle, but recently it has been suggested that it may be secondary to a neuronal defect or to a generalized disorder of protein synthesis and membrane. However, to date there is no proof to support unequivocally any of these theories. A higher incidence of mental retardation and decreased intellectual functioning has been reported in the medical literature of Duchenne muscular dystrophy patients than for normals or other control groups. Recently there has been strong evidence to suggest that verbal ability, as reflected by the WISC Verbal scale IQ, may be more commonly and significantly impaired in Duchenne muscular dystrophy patients than is nonverbal ability, as reflected by the Performance scale IQ. This article presents a comprehensive review of data from the literature on intellectual functioning in Duchenne muscular dystrophy, as well as methodological issues involved in assessment of intelligence in this population. The intent is to provide a basis for future attempts to relate the intellectual deficit in Duchenne muscular dystrophy to neuropsychological and neurobiological parameters of the disease. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Commentary: extraocular muscle sparing in muscular dystrophy: a critical evaluation of potential protective mechanisms

Muscles or muscle groups exhibiting responses to neuromuscular disease that are unlike those of other skeletal muscles may provide novel information about pathogenesis leading to improved treatment strategies. The author's laboratory studies the relationship between the unique phenotype of the extraocular muscles and their selective sparing or targeting in neuromuscular disease. This commentary evaluates the evidence for and against four hypotheses for the selective protection of extraocular muscle in Duchenne muscular dystrophy (DMD) and merosin-deficient congenital muscular dystrophy (CMD).     

Asymptomatic Becker muscular dystrophy: expression of dystrophin and dystrophin-related protein

We report a patient with systemic lupus erythematosus (SLE), who had developed metabolic alkalosis during plasmapheresis. The metabolic alkalosis could be promptly corrected by reducing the amount of citrate load. The development of metabolic alkalosis can be explained by the citrate load during plasmapheresis. Careful monitoring of acid base status is mandatory in patients with limited renal function and the reduction of citrate load may be advisable in plasmapheresis.     

Molecular diagnosis of Duchenne muscular dystrophy in Singapore

TL-transgenic mice expressing the thymus leukemia antigen demonstrate a lack of viral clearance following cutaneous HSV infection of the footpad. In this study, both uninfected and HSV-infected TL-transgenic mice demonstrate increased concentrations of IL-4 as well as decreased concentrations of IFN-gamma which may possibly underlie the impairment of viral clearance. Furthermore, lymphocytes from HSV-infected nontransgenic mice, adoptively transferred into HSV-infected TL-transgenic mice, promoted viral clearance and led to an increase in IFN-gamma production. Transgenic mice which were subcutaneously injected with IFN-gamma in the right footpad were also capable of clearing the viral challenge; however, clearance was restricted solely to the right footpad. These studies support the possibility of perturbations in the immune system of TL-transgenic mice and effectively demonstrate the utility of this model system in the study of HSV clearance, persistence, and potential spontaneous reactivation. Moreover, the TL-transgenic animals may provide a useful model system for additional studies requiring a host system skewed toward a Th2 phenotype.