Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029089 (ophthalmoplegia)
 3,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In muscle, the neural cell adhesion molecule (NCAM) is known to be expressed in denervated and regenerating fibers. Our present study, performed with immunohistochemical detection procedures, attempts to demonstrate the expression of NCAM in mitochondrial myopathy. Biopsy specimens from 29 patients were investigated. The following conditions were represented: nonweak control subjects (8 cases), chronic progressive external ophthalmoplegia (7 cases), Kearns-Sayre syndrome (5 cases), unclassified mitochondrial myopathy (2 cases), idiopathic polymyositis (7 cases). We demonstrate the expression of NCAM in mitochondrial myopathy. But NCAM is expressed in ragged-red fibers both in mitochondrial and idiopathic inflammatory myopathy. Furthermore, NCAM-immunoreactive fibers are more abundant than ragged-red and cytochrome-c-deficient fibers. Thus, we conclude that NCAM expression precedes histochemical and enzyme-histochemical demonstrable mitochondrial abnormalities. NCAM expression may reflect compensatory regenerating tendency of ragged-red fibers. Vimentin expression in mitochondrial myopathy favors this view. Probably, NCAM plays a role in the enrichment of abnormal mitochondria as a compensatory process for the biochemical deficit. The expression of NCAM in mitochondrial myopathies suggests that NCAM is related to the pathophysiology of these diseases and can be a helpful clue in the diagnosis of mitochondrial myopathy. But NCAM expression is not a specific phenomenon in mitochondrial myopathy, because in secondary mitochondrial changes like in idiopathic polymyositis NCAM expression is observed, too.
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PMID:Expression of NCAM (neural cell adhesion molecule) in mitochondrial myopathy. 860 39

We studied muscle fatigue and serum lactate and pyruvate levels in 20 patients with mitochondrial myopathy with progressive external ophthalmoplegia (PEO). Fatigue was assessed in the adductor pollicis muscle (AP) using a low-intensity exercise protocol (20 min). Forces (TFs) and relaxation times of ulnar nerve evoked twitches, compound muscle action potentials (CMAPs), and maximal voluntary contractions (MVCs) were monitored. Serum lactate and pyruvate levels were independently measured at rest and after exercise on a bicycle (15 min, 30 W). Most patients showed abnormal fatigue of the AP with a reduction of TFs and MVCs and normal CMAPs. The reduced TFs were significantly correlated with lactate levels at rest (r= - 0.60, P<0.05) and less so with those after exercise (r=- 0.47,P<0.05). Pyruvate levels revealed a similar correlation although they were widely scattered. We conclude that abnormal fatigue in PEO is metabolic, is localized beyond the muscle fiber membrane, and involves the electrome-chanical coupling and the contractile apparatus. Serum lactate levels at rest are good predictors of fatigue in PEO.
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PMID:Muscle fatigue, lactate, and pyruvate in mitochondrial myopathy with progressive external ophthalmoplegia. 862 24

We analysed the mitochondrial genome of one patient with chronic and progressive bilateral ophthalmoplegia. This patient also had abnormal EKG showing cardiac conduction defects and pigmentary retinopathy, suggestive of the Kearns-Sayre syndrome. On muscle biopsy, with Gomori trichrome stain, the fibers showed an increase in red-staining material in the intermyofibrillary network and the subsarcolemmal region. On electron microscopy, aggregations of abnormal mitochondria were demonstrated, confirming the diagnosis of mitochondrial myopathy. Analysis of mitochondrial DNA (mtDNA) from the patient and her mother showed no deleted mtDNA.
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PMID:Mitochondrial genome analysis in Kearns-Sayre syndrome. 862 98

The Authors reports a case of myopathy with severe scoliosis which can be classified within the context of chronic progressive external ophthalmoplegia (CPEO) and discusses the complex etiopathogenetic, histological and clinical aspects of this mitochondrial myopathy. In particular, they underlines the severity of the scoliosis and muscular, bone and respiratory symptoms in this case and the important role played by histological, histochemical and biochemical aspects in the diagnosis.
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PMID:[A case of chronic progressive external ophthalmoplegia with severe scoliosis]. 868 4

Molecular diagnosis for mitochondrial diseases offers a powerful means to clarify that mitochondrial DNA (mtDNA) defects have different characteristics from those of nuclear DNA. Regarding the relationship between genotype and phenotype, there is a dual heterogeneity. It means that one mutation, for example, a 3243 mutation, has several clinical phenotypes, including MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes), myopathy only, diabetes and/or deafness and even CPEO (chronic progressive external ophthalmoplegia). Conversely, one phenotype, for instance, MELAS has several genetypes; 3243, 3271, and 3291 mutations. The second unique event in mitochondrial DNA mutation is heterogenous distribution of mutant mtDNA in a mitochondrion or a cell that is called heteroplasmy. The extend of heteroplasmy seems different from tissue to tissue providing clues to explain the variability of tissue impairment and heterogenous clinical symptoms. The above evidence suggests that we should take care in selecting tissues to be tested. The third problem remained is on maternal inheritance. It makes the genetic counselling on mitochondrial diseases at clinics difficult and laborious. In conclusion, mtDNA analysis must be used as a last resort to get final diagnosis.
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PMID:[Mitochondrial encephalomyopathies: 3243 mutation as a central matter]. 875 18

Blink reflex (BR) was studied in 17 patients with histochemically and genetically confirmed mitochondrial myopathy (MM). Fourteen patients had chronic progressive external ophthalmoplegia (CPEO) associated with a mild to moderate craniosomatic myopathy without any symptoms or signs of central nervous system (CNS) involvement, 2 myoclonic epilepsy with ragged red fibers syndrome, and 1 Kearns-Sayre syndrome. The mean latencies of the early (R1) and late (R2) responses were prolonged (P < 0.01 and P < 0.001, respectively), and the corresponding amplitudes decreased (P < 0.001). Increased habituation of the reflex was clearly observed in 10 out of 14 patients tested (71.4%), 9 of whom presented CPEO. These findings suggest that the brain stem reticular network is in a state of basal inhibition which is presumably due to a subclinical impairment of the cerebral cellular metabolism. Multimodal evoked potentials revealed abnormalities suggestive of CNS involvement in 7 out of 17 patients (41.2%), 4 of whom had CPEO. These observations document the validity of BR in detecting clinically silent brain stem impairment in patients with apparently pure MM and provide important clues for a further understanding of the underlying pathophysiology.
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PMID:Reduced brain stem excitability in mitochondrial myopathy: evidence for early detection with blink reflex habituation studies. 894 Dec 73

Sporadic progressive external ophthalmoplegia and Kearns-Sayre syndrome are usually associated with single large-scale mitochondrial DNA deletions in muscle. In progressive external ophthalmoplegia with autosomal dominant inheritance, multiple mitochondrial DNA deletions have been reported. We studied several members of a Swedish family with autosomal dominant progressive external ophthalmoplegia and multiple mitochondrial DNA deletions by polymerase chain reaction analysis of single muscle fibers and by in situ hybridization, combined with enzyme histochemical analysis. Muscle fiber segments with deficiency of cytochrome c oxidase, which is partially encoded by mitochondrial DNA, had accumulated mitochondrial DNA with deletions and showed reduced levels of wild-type mitochondrial DNA. The deletions varied between individual muscle fibers. There was one predominant deletion in each cytochrome c oxidase-deficient muscle fiber segment. Sequencing of the deletion breakpoints showed that most but not all of the deletions were flanked by direct repeats. Young, clinically affected individuals of this family without limb muscle symptoms did not show mitochondrial DNA deletions or cytochrome c oxidase-deficient muscle fibers. Our results indicate that a nuclear factor predisposes to the development of somatic multiple mitochondrial DNA deletions. Mitochondrial DNA with multiple different deletions shows clonal expansion, which leads to mitochondrial myopathy with ragged-red fibers and muscle weakness.
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PMID:Clonal expansion of mitochondrial DNA with multiple deletions in autosomal dominant progressive external ophthalmoplegia. 895 8

We report a 64-year-old man presenting with multiple symmetric lipomatosis (MSL) and mitochondrial encephalomyoneuropathy. The diagnosis of a mitochondrial cytopathy was based on the typical clinical symptoms and signs, including chronic progressive external ophthalmoplegia, hearing impairment, cerebellar ataxia, proximal myopathy, and polyneuropathy, and on molecular genetic and histological examinations. As a unique finding, the A-->G(8344) myoclonus epilepsy and ragged-red fibers point mutation was found in peripheral nerve, muscle, and adipose tissue. Muscle biopsy revealed multiple ragged-red fibers and other morphological signs of a mitochondrial myopathy. Sural nerve biopsy demonstrated a mixed axonal and demyelinating neuropathy with extensive loss of myelinated fibers and conspicuous onion bulb formations, as well as structural mitochondrial abnormalities on electron microscopy. These findings clearly demonstrate mitochondrial dysfunction in muscle, adipose tissue, and for the first time also in nervous tissue of an MSL patient, and strongly support the concept of mitochondrial cytopathy as one of the possible causes of multiple symmetric lipomatosis.
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PMID:Mitochondrial dysfunction with myoclonus epilepsy and ragged-red fibers point mutation in nerve, muscle, and adipose tissue of a patient with multiple symmetric lipomatosis. 917 55

We report a short-term double-blind, crossover study of CoQ10 in 8 patients with mitochondrial encephalomyopathies. Four patients had myoclonus epilepsy with ragged-red fibers syndrome, 3 had mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes syndrome, and 1 had chronic progressive external ophthalmoplegia with myopathy. A trend of effectiveness of CoQ10 in several parameters was noted. Fatigability of daily activities was alleviated. The endurance to muscle exercise was augmented. Global muscle strength scored by Medical Research Council scale was increased. The extent of elevation in serum lactate and pyruvate levels after exercise was decreased. However, only the global MRC index score had a statistical significance (p < 0.05). There were no side effects during therapy. The serum CoQ10 levels were significantly lower in patients than in normal controls before CoQ10 treatment and increased significantly after treatment.
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PMID:Coenzyme Q10 treatment in mitochondrial encephalomyopathies. Short-term double-blind, crossover study. 920 60

We measured oxygen consumption in the exercising lower limb by using noninvasive tissue oximetry with the near-infrared spectra of hemoglobin in the quadriceps muscle during bicycle ergometer exercise in four normal controls and three patients with chronic progressive external ophthalmoplegia (CPEO) as well as one patient with mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS). Normal controls showed constant oxygenation during exercise and a rapid recovery after exercise. However, all four patients with mitochondrial myopathy showed abnormal oxygenation during exercise and a slow recovery afterward. The results reflected the defect in oxidative phosphorylation and the impairment in oxygen utilization in those patients. The distinctive patterns of imbalance between oxygen delivery and utilization correlated well with the severity of mitochondrial myopathy as judged by the sum of the serum lactate and pyruvate content during exercise. Noninvasive tissue oximetry may be useful to measure the severity of myopathy and exercise intolerance in patients with mitochondrial myopathy.
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PMID:Measurement of tissue oxygen consumption in patients with mitochondrial myopathy by noninvasive tissue oximetry. 978 91


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