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)

A patient is described who has features of Pearson syndrome and who presented in the neonatal period with a hypoplastic anemia. He later developed hepatic, renal, and exocrine pancreatic dysfunction. At the age of 5 years he developed visual impairment, tremor, ataxia, proximal muscle weakness, external ophthalmoplegia, and a pigmentary retinopathy (Kearns-Sayre syndrome). Muscle biopsy confirmed the diagnosis of mitochondrial myopathy. Analysis of mtDNA from leukocytes and muscle showed mtDNA heteroplasmy in both tissues, with one population of mtDNA deleted by 4.9 kb. The deleted region was bridged by a 13-nucleotide sequence occurring as a direct repeat in normal mtDNA. Both Pearson syndrome and Kearns-Sayre syndrome have been noted to be associated with deletions of mtDNA; they have not previously been described in the same patient. These observations indicate that the two disorders have the same molecular basis; the different phenotypes are probably determined by the initial proportion of deleted mtDNAs and modified by selection against them in different tissues.
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PMID:Pearson syndrome and mitochondrial encephalomyopathy in a patient with a deletion of mtDNA. 198 62

We studied a large family with a dominantly inherited mitochondrial myopathy characterized by progressive external ophthalmoplegia, dysphagia, cataract, lactic acidosis, exercise intolerance, and early death. Morphologic studies of muscle biopsies suggested mitochondrial heteroplasmy and revealed ragged-red fibers and decreased histochemical reactions for cytochrome c oxidase and succinate dehydrogenase. Biochemistry showed a partial defect of cytochrome c oxidase and a mild generalized reduction of other mitochondrial enzymes requiring mitochondrial DNA-encoded subunits. Southern blot analysis and PCR amplification showed mitochondrial DNA deletions in muscle of all affected members, but not in lymphocytes or fibroblasts, suggesting a tissue-specific distribution. Deletions were multiple and seemed to increase with time and to correlate with the severity of the disease.
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PMID:Dominantly inherited mitochondrial myopathy with multiple deletions of mitochondrial DNA: clinical, morphologic, and biochemical studies. 206 33

We describe a 55 years old man affected by eyelid ptosis, mild ophthalmoplegia externa and severe dysphagia owing to pharyngoesophageal dyskinesia. Skeletal and eyelid constrictor muscles EMG showed myogenic alterations. Muscle histological findings of ragged red fibers and oxidative histochemical alterations, together with ultrastructural investigation clue for mitochondrial myopathy diagnosis. This, considering the unusual clinical aspects of the case, confirms as mitochondrial disease can widely vary in their phenotypical expression.
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PMID:[Mitochondrial oculopharyngeal myopathy: description of a case]. 210 41

Mitochondrial encephalomyopathies are usually divided into three distinct clinical subgroups: (1) mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS); (2) myoclonus epilepsy associated with ragged-red fibres (MERRF); and (3) chronic progressive external ophthalmoplegia (CPEO) including Kearns-Sayre syndrome. Large deletions of human mitochondrial DNA and a transition mutation at the mitochondrial transfer RNALys gene give rise to CPEO including Kearns-Sayre syndrome and MERRF, respectively. Here we report an A-to-G transition mutation at nucleotide pair 3,243 in the dihydrouridine loop of mitochondrial tRNA(Leu)(UUR) that is specific to patients with MELAS. Because this mutation creates an ApaI restriction site, we could perform a simple molecular diagnostic test for the disease. The mutation was present in 26 out of 31 independent MELAS patients and 1 out of 29 CPEO patients, but absent in the 5 MERRF and 50 controls tested. Southern blot analysis confirmed that the mutant DNA always coexists with the wild-type DNA (heteroplasmy).
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PMID:A mutation in the tRNA(Leu)(UUR) gene associated with the MELAS subgroup of mitochondrial encephalomyopathies. 171 Mar 18

We carried out a histological examination of the extraocular muscles (EOMs) in a case of myoclonus epilepsy associated with ragged-red fibers (MERRF) and two cases of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), which did not manifest external ophthalmoplegia clinically. By light microscopy, many granular and vesicular fibers were seen associated with endomysial fibrosis. Electron microscopy revealed that the fibers showed prominent accumulation of abnormal mitochondria, extensive loss of myofibrils, proliferation of free sarcoplasmic reticulum and an increased amount of lipid vacuoles. These changes were more pronounced in MELAS than in MERRF. Hirano bodies were often seen in the subsarcolemmal area of muscle fibers and also in the intramuscular myelinated nerve fibers and axon terminals. These findings suggest the presence of mitochondrial myopathy of the EOMs in cases of MELAS and MERRF.
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PMID:Involvement of extraocular muscle in mitochondrial encephalomyopathy. 211 41

Respiratory chain enzymes were studied in isolated mitochondria of two patients with mitochondrial myopathy. Both patients had been suffering from chronic progressive external ophthalmoplegia and abnormal muscular fatigability since late childhood. One of the patients exhibited the complete triad of symptoms characteristic of Kearns-Sayre syndrome. Venous lactate levels at rest and during minimal exercise were increased in both patients. Histochemical examination of muscle revealed ragged red fibres and intermingled fibres negative for cytochrome c oxidase. Biochemical studies showed decreased activities of complex I and complex IV of the respiratory chain in both patients. Reduced minus oxidized spectra of mitochondrial cytochromes revealed a decreased content of cytochrome aa3 in only one patient, but a normal content in the other. A combined deficiency of complexes I and IV in muscle might either be due to a deficiency of a single subunit common to both complexes or to a coincidental deficiency of both complexes expressed either in the same or in different fibres.
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PMID:Partial deficiency of complexes I and IV of the mitochondrial respiratory chain in skeletal muscle of two patients with mitochondrial myopathy. 254 13

A 41-year-old female of mitochondrial myopathy characterized by recurrent paralytic ileus and atonic bladder with the evidence of peripheral nerve involvement was described. This patient was admitted to our hospital because of the episode of paralytic ileus and atonic bladder at the age of 40 and 41 (1987). She had noticed sporadic headache from 1967, constipation from 1977, tinnitus and hearing disturbance from 1984. One month after her second admission in 1987, her symptoms of paralytic ileus and atonic bladder gradually disappeared. She was then transferred to the department of neurology for the evaluation of underlining neurological disorders. Neurological examination revealed dementia, oro-lingual dyskinesia, and proximal muscular weakness. However, none of the following signs or symptoms were observed; Ophthalmoplegia, blepharoptosis, retinitis pigmentosa, myoclonus, cerebellar ataxia, sensory disturbance, and orthostatic hypotension. Deep tendon reflexes were normal. Planter responses were flexor. Pyruvate and lactate were elevated in both serum and cerebrospinal fluid. Brain CT scan displayed moderate cerebral atrophy and basal ganglia calcifications. EMG was normal except for the external anal sphincter muscles which showed a denervation pattern. Motor nerve conduction velocity was normal in the right median and the right peroneal nerves. Sensory nerve conduction velocity was also normal in the right median and the right sural nerves. However, the amplitude of sensory potential was low in both these nerves. Atonic type of neurogenic bladder was noted on cystometry. There was a lack of voiding desire. The number of active sweat glands iontophoretically stimulated by pilocarpine was reduced. The most prominent feature of the muscle biopsy (the left biceps brachii) was myopathic changes with ragged-red fibers.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Paralytic ileus and atonic bladder in a case of mitochondrial encephalomyopathy--electrophysiological, chemical and pathological study with evidence of the peripheral nerve involvement]. 255 55

Two patients (a 50-year-old and a 35-year-old men) with focal cytochrome c oxidase deficiency, manifesting ptosis and external ophthalmoplegia of 13 and 6 years' duration, respectively, were reported. Patient 1 (a 50-year-old male) had also slight muscular weakness of the proximal limb and neck flexor muscles. Diagnosis of myasthenia gravis had been made on the clinical findings including ptosis and external ophthalmoplegia, diurnal fluctuation of symptoms, and equivocal positive Tensilon test. However, waning phenomenon on repetitive nerve stimulation or elevation of titer of the anti-acetylcholine receptor antibody was not detected on both patients. Needle EMG showed mild myopathic changes. Finally, pathological and biochemical analyses of the biopsied muscles confirmed the diagnosis of mitochondrial myopathy (focal cytochrome c oxidase deficiency).
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PMID:[Two cases of mitochondrial myopathy (focal cytochrome c oxidase deficiency), long-term follow-up on a diagnosis of ocular type myasthenia gravis]. 255 82

Ragged-red fibers (RRFs) are mainly seen in mitochondrial myopathy and related to biochemical defects in electron transfer chain on some occasions. Recently, some papers reported the occurrence of RRFs in the biopsied muscle of myotonic dystrophy (MyD). To examine whether the mitochondrial function is disturbed in MyD, we have studied the biopsied muscles of 12 cases with MyD (10 males and 2 females averaging 38 years of age) morphologically and mainly biochemically. RRFs, ranging from 2--20% of the muscle fibers, were identified in 5 out of 12 cases. On electron microscopy, these fibers had aggregated abnormally enlarged mitochondria with dene bodies, concentrically whirled membranous cristae and paracrystalline inclusions. Clinically, 4 of 5 cases with RRFs had mild to moderate and only 2 of 7 without RRFs had ophthalmoplegia. Bicycle ergometer exercise test showed abnormal increase of lactate/pyruvate ratio in three cases with RRFs. Histochemically, cytochrome c oxidase (CCO) activity was absent selectively in all of the RRFs. Immunohistochemical staining showed the presence of CCO protein by using monoclonal antibody which was specific to CCO subunit IV. Biochemical study with crude muscle extract of 11 cases of MyD showed decreases in NADH dehydrogenase, NADH CoQ reductase, succinate CoQ reductase (SCR), CCO, carnitine actyl transferase activities in most of cases regardless RRFs. To avoid the influence possibly derived from the various stages of muscle degeneration in the biopsied specimens, we calculated the ratio of the enzyme activities compared with succinate dehydrogenase which was located in the electron transfer chain and did not show any statistical difference regardless of RRFs.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[A study of mitochondrial electron transfer chain in myotonic dystrophy]. 259 36

Analysis of mitochondrial DNA (mtDNA) in muscle and blood from 72 patients with mitochondrial myopathy showed that 30 had major deletions of a variable proportion of muscle mtDNA. All of these 30 patients presented with progressive external ophthalmoplegia and limb weakness, and 8 had the additional features of the Kearns-Sayre syndrome. Of the 42 patients without detectable muscle mtDNA deletions, 10 had progressive external ophthalmoplegia and limb weakness, 2 had the Kearns-Sayre syndrome, 11 had limb weakness without extraocular involvement, and 19 had multisystem disorders predominantly affecting the central nervous system. Only 2 patients with mtDNA deletions had clinically affected relatives, compared with 10 of those without deletions. In the 4 patients with polarographic defects exclusively involving complex I (NADH coenzyme Q reductase), the deleted protein-coding genes were confined to those for complex I subunits. Thirteen other patients with apparently identical deletions had variable clinical and biochemical features. Immunoblots of complex I polypeptides from patients with deletions were either indistinguishable from controls or showed only a mild generalized decrease in all identifiable subunits.
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PMID:Mitochondrial myopathies: clinical and biochemical features of 30 patients with major deletions of muscle mitochondrial DNA. 260 80


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