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)

Three patients with mitochondrial myopathies and progressive external ophthalmoplegia had repeated episodes of respiratory failure requiring assisted ventilation. Studies in these patients and asymptomatic family members, as well as a sporadic case of Kearns-Sayre syndrome, demonstrated markedly depressed ventilatory drive responses to hypoxia. In 2 patients, there was also decreased drive to hypercapnia. The reduced ventilatory drive appears to be due to an altered neural control system that may cause episodic life-threatening hypoventilation occurring especially in relation to surgery, sedation, or intercurrent infection.
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PMID:Recurrent respiratory insufficiency and depressed ventilatory drive complicating mitochondrial myopathies. 229 55

Mitochondrial myopathies can affect the skeletal muscle, the central or peripheral nervous system, and they may be associated with chronic progressive external ophthalmoplegia (CPEO). In 7/29 patients with mitochondrial myopathies and CPEO a cardiac involvement (Kearns-Sayre syndrome) was found: incomplete right bundle branch block (n = 1), right bundle branch block (n = 1), left anterior fascicular block and right bundle branch block (n = 2), complete atrioventricular block (n = 3); congestive cardiac failure (ejection fraction 40%) (n = 2); 3/10 patients had prolonged infranodal conduction on His-bundle electrography (HV-interval 60 ms). The cardiac involvement in ophthalmoplegia plus is characterized by progressive impairment of fascicular conduction. The need for prophylactic pacemaker implantation appears to exist in patients with bifascicular block and prolonged His-ventricle conduction.
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PMID:[Indications for pacemaker therapy in ophthalmoplegia plus and Kearns-Sayre syndrome]. 231 77

Two clinico-pathological cases of Kearns-Sayre syndrome are reported. In both cases the typical triad (progressive external ophthalmoplegia, heart block, retinitis pigmentosa) was present and spongiosis was the main pathological finding. In one case there was also a marked capillary proliferation, significance of which is discussed. A deletion of the mitochondrial DNA was found in the muscle, spinal cord and brain of this last case.
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PMID:Kearns-sayre syndrome. Two clinico-pathological cases. 235 83

By using a combination of Southern blot hybridization analysis, polymerase-chain reaction amplification, and direct nucleotide sequencing, we studied deletions of mitochondrial DNA (mtDNA) in several nonfamilial patients with progressive external ophthalmoplegia and Kearns-Sayre syndrome, and in some of their direct relatives. Results suggest that the heteroplasmic mtDNA populations are already present at a very early stage of development, and that there is no direct transmission of mtDNA heteroplasmy by maternal inheritance.
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PMID:Tissue distribution and transmission of mitochondrial DNA deletions in mitochondrial myopathies. 237 42

The Kearns-Sayre syndrome is identified by the triad of progressive external ophthalmoplegia, atypical pigmentary retinopathy, and conduction disturbances. In addition, clinical manifestations may include mental retardation, sensorineural deafness, cerebellar ataxia, and facial and peripheral muscle weakness. Morphologic alterations in skeletal muscle may be characterized by ragged-red fibers. Two patients with Kearns-Sayre syndrome underwent electrophysiological examination. The first patient had a first and second degree AV block (Mobitz type II), right bundle branch block, and left axis deviation. The His-bundle electrogram showed a prolonged HV interval as a hint at an intraventricular conduction delay. The signal-averaging technique and endocardial mapping revealed ventricular after-depolarizations. The second patient had an unsuspicious ECG, recurrent atrial tachycardias, normal atrial and ventricular conduction, and after-depolarizations in endocardial mapping. Two months later he showed a second degree AV block combined with clinical symptoms. Pacemakers were implanted in both patients. Beside disturbances of the conduction system in both patients signs of electrical instability of the myocardium were found. In this way the Kearns-Sayre syndrome may be seen as a form of cardiomyopathy.
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PMID:[Electrophysiologic findings in patients with Kearns-Sayre syndrome--report on 2 cases]. 240 85

The medical and dental problems of patients with Kearns-Sayre syndrome are presented. Kearns-Sayre syndrome is a multisystemic disorder involving chronic progressive external ophthalmoplegia, pigmentary degeneration of the retina (retinitis pigmentosa), and complete heart block. A case is presented to demonstrate problems common to the management of these patients as well as appropriate treatment recommendations.
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PMID:Kearns-Sayre syndrome. 253 99

We investigated the correlations of deletions of mitochondrial DNA in skeletal muscle with clinical manifestations of mitochondrial myopathies, a group of disorders defined either by biochemical abnormalities of mitochondria or by morphologic changes causing a ragged red appearance of the muscle fibers histochemically. We performed genomic Southern blot analysis of muscle mitochondrial DNA from 123 patients with different mitochondrial myopathies or encephalomyopathies. Deletions were found in the mitochondrial DNA of 32 patients, all of whom had progressive external ophthalmoplegia. Some patients had only ocular myopathy, whereas others had Kearns-Sayre syndrome, a multisystem disorder characterized by ophthalmoplegia, pigmentary retinopathy, heart block, and cerebellar ataxia. The deletions ranged in size from 1.3 to 7.6 kilobases and were mapped to different sites in the mitochondrial DNA, but an identical 4.9-kilobase deletion was found in the same location in 11 patients. Biochemical analysis showed decreased activities of NADH dehydrogenase, rotenone-sensitive NADH-cytochrome c reductase, succinate-cytochrome c reductase, and cytochrome c oxidase, four enzymes of the mitochondrial respiratory chain containing subunits encoded by mitochondrial DNA. We conclude that deletions of muscle mitochondrial DNA are associated with ophthalmoplegia and may result in impaired mitochondrial function. However, the precise relation between clinical and biochemical phenotypes and deletions remains to be defined.
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PMID:Mitochondrial DNA deletions in progressive external ophthalmoplegia and Kearns-Sayre syndrome. 230

31P-NMR spectra were obtained from the quadriceps femoris muscle (at rest and after aerobic exercise) of the 7 cases of mitochondrial myopathies (2 cases of mitochondrial encephalomyopathy and lactic acidosis(MELA), 1 case of myoclonus epilepsy with regged red fiber, 1 case of Kearns-Sayre syndrome, 3 cases of progressive external ophthalmoplegia), using superconducting whole body MR (Magnetom, Siemens). One case showed abnormally low Pcr/Pi ratio in the resting state. An aerobic exercise using ergometer was performed on the other 6 patients. Three of them demonstrated significant reduction and delayed recovery of the Pcr/Pi ratio after exercise. This reduction was not detected in the control subjects. Histological studies of biopsied muscles revealed ragged red fibers in all the cases, the number varies, however, from 0.5 to 15.3 per cent of the total fibers. Abnormalities in the Pcr/Pi ratio of phosphorus spectra, in resting state or after exercise, tend to be observed in patients showing abundant ragged red fibers. Focal cytochrome c oxidase deficiency with relatively small amount of ragged red fibers (less than 10 per cent of the total fibers) was histologically noted in five of our patients, excluding 2 MELA patients. Biochemical assay of mitochondria enzyme was normal. It has been assumed that these patients have no primary defect in energy metabolism and the occasionally observed cytochrome c oxidase deficient fibers are non-specific findings probably caused by some devastating process occurring in these fibers. However, our present studies revealed abnormal reduction and delayed restoration of the Pcr/Pi ratio in 2 out of 5 focal cytochrome c oxidase deficiency cases.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[31P-NMR spectroscopy of mitochondrial myopathies: the relation between abnormal energy metabolism and muscle biopsy findings]. 254 6

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

The muscle mitochondria of a patient with Kearns-Sayre/chronic external ophthalmoplegia plus syndrome were found to be completely deficient in respiratory complex I activity and partially deficient in complex IV and V activities. Treatment of the patient with coenzyme Q10 and succinate resulted in clinical improvement of respiratory function, consistent with the respiratory deficiencies. Restriction enzyme analysis of the muscle mtDNA revealed a 4.9-kilobase deletion in 50% of the mtDNA molecules. Polymerase chain reaction analysis demonstrated that the deletion was present in the patient's muscle but not in her lymphocytes or platelets. Furthermore, the deletion was not present in the muscle or platelets of two sisters. Hence, the mutation probably occurred in the patient's somatic cells. Direct sequencing of polymerase chain reaction-amplified DNA revealed a 4977-base-pair deletion removing four genes for subunits of complex I, one gene for complex IV, two genes for complex V, and five genes for tRNAs, which paralleled the respiratory enzymes affected in the disease. A 13-base-pair direct repeat was observed upstream from both breakpoints. Relative to the direction of heavy-strand replication, the first repeat was retained and the second repeat was deleted, suggesting a slip-replication mechanism. Sequence analysis of the human mtDNA revealed many direct repeats of 10 base pairs or greater, indicating that this mechanism could account for other reported deletions. We postulate that the prevalence of direct repeats in the mtDNA is a consequence of the guanine-cytosine bias of the heavy and light strands.
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PMID:Spontaneous Kearns-Sayre/chronic external ophthalmoplegia plus syndrome associated with a mitochondrial DNA deletion: a slip-replication model and metabolic therapy. 255 97


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