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)

We have investigated a 15 year old girl with progressive external ophthalmoplegia, including bilateral ptosis and retinal rod and cone cell dysfunction with atypical retinal pigmentation, complicated by cerebellar ataxia, partial cardiac conduction block, and diabetes mellitus. In infancy she had a severe crisis of bone marrow depression, and as a child she suffered from hypersensitivity to light, increasing fatigue, and vertigo, signs that were initially though to be psychosomatic. Histological examination showed mitochondrial myopathy, and subsequent mitochondrial DNA (mtDNA) analysis showed a deletion of approximately 5500 base pairs in 35 to 40% of her muscle mtDNA. We therefore conclude that this patient has developed the Kearns-Sayre syndrome after a Pearson syndrome-like crisis in her first year of life.
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PMID:Juvenile Kearns-Sayre syndrome initially misdiagnosed as a psychosomatic disorder. 815 37

We have investigated nine children with infantile onset of mitochondrial myopathy and two adults with myoclonus epilepsy and ragged-red fibers (MERRF) and chronic progressive external ophthalmoplegia (CPEO), respectively. These patients lacked any of the previously known pathogenic tRNA mutations. Southern blot analysis of muscle mtDNA revealed no deletions. The tRNA genes of muscle mtDNA were sequenced. Restriction enzyme analysis of PCR fragments was performed to verify the presence of the mutations identified by automatic sequencing. Several tRNA mutations were found, but they were all homoplasmic. Furthermore, the mutations were either present in controls or did not change nucleotides conserved between species. This strongly suggests that none of the tRNA mutations identified in the 11 patients with mitochondrial encephalomyopathy was pathogenic. It can thus be concluded that mitochondrial tRNA mutations and mtDNA deletions probably are an infrequent cause of mitochondrial disorders in infants. Patients with MERRF and CPEO may lack both pathogenic point mutations of tRNA genes and deletions of mtDNA.
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PMID:Automatic sequencing of mitochondrial tRNA genes in patients with mitochondrial encephalomyopathy. 815 39

Fourteen patients (10 boys, 4 girls) aged from 4 months to 14 years old were diagnosed with mitochondrial disease based on the clinical manifestations together with abnormal muscle mitochondrial morphologies. Their clinical diagnoses included Leigh syndrome, three; Menkes' syndrome, three; Kearns-Sayre syndrome, two; myoclonic epilepsy with ragged fibres, one; and infant-onset progressive myoclonic epilepsy, one; fatal infantile mitochondrial myopathy, one; fatty acid oxidation defect, two; and myopathy with cardiopathy, one. Organs involved other than muscles included central nervous system, ten; heart, six; eye, two; liver, two; and kidney, two. Clinical manifestations varied to include hypotonia, seizures, myoclonus, mental retardation, nystagmus, ataxia, ptosis, ophthalmoplegia, retinal degeneration, muscle atrophy, spasticity etc. Nine had an abnormal rise in lactate after glucose loading. Ragged-red fibres were found in four patients. Abnormal mitochondrial morphology included abnormal accumulation, abnormal cristae pattern of tubular, concentric, or parallel form, some contained osmiophilic inclusion bodies. One patient of Leigh syndrome had had brain necropsy which showed intramyelin splitting of myelinated axons.
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PMID:Clinical manifestation of mitochondrial diseases in children. 821 54

Recent discoveries in mitochondrial clinical genetics have revealed that a broad spectrum of clinical phenotypes are associated with mutations in mitochondrial DNA. Diseases caused by mutations in mitochondrial DNA are by nature quantitative. Myoclonic epilepsy and ragged-red fiber disease are caused by a mutation in the transfer RNA gene lysine. Although everyone in a maternal lineage will harbor the same mutation, the nature and severity of the symptoms vary markedly among individuals. This variability correlates with the inherited percentage of mutations in the individual's mitochondrial DNA and the individual's age. Age-related expression of mitochondrial disease has also been demonstrated for mitochondrial DNA deletions. Although deletions that retain both origins of replication result in late-onset disease because of the progressive enrichment of the deleted mitochondrial DNA, a 10.4-kb deletion that lacks the light-strand replication origin and maintains a stable mutant percentage in both tissues and cultured cells has been discovered. This deletion is associated with adult-onset diabetes and deafness, but not with ophthalmoplegia, ptosis, or mitochondrial myopathy. Biochemically, it causes a generalized defect in mitochondrial protein synthesis and oxidative phosphorylation. The age-related decline in oxidative phosphorylation could reflect the accumulation of somatic mitochondrial DNA mutations. Inhibition of oxidative phosphorylation stimulates this accumulation. The general paradigm for mitochondrial DNA diseases may be that inherited mutations inhibit the electron transport chain. This damages the mitochondrial DNA, further reducing oxidative phosphorylation. Ultimately, oxidative phosphorylation drops below the expression threshold of cells and tissues, and clinical symptoms appear.
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PMID:Mitochondrial DNA mutations in epilepsy and neurological disease. 829 23

It has been clarified at the molecular and genetic levels that mitochondrial DNA (mt DNA) and/or nuclear DNA mutations are the cause of a group of diseases called mitochondrial cytopathies or mitochondrial myopathies. We review: (1) the characteristics of mtDNA and its inheritance, (2) the mtDNA deletions in Kearns-Sayre syndrome and chronic progressive external ophthalmoplegia, (3) the point mutations in mtDNA tRNA(Leu(UUR)) gene at positions 3,243 and 3,271 in mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), (4) the mtDNA deletions and point mutations in patients with dilated or hypertrophic cardiomyopathy, and (5) the mtDNA deletions or point mutation in three pedigrees with maternally transmitted non-insulin-dependent diabetes mellitus.
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PMID:[Molecular biology of mitochondrial DNA and mutations in mitochondrial cytopathy]. 832 Aug 24

We reported a senile male patient with progressive external ophthalmoplegia (PEO) and myositis. The ophthalmoplegia was severe, but other neuromuscular features were nearly normal. Muscle enzymes in serum were moderately elevated. Autoimmune, endocrinological or malignant diseases were not observed during the previous 4 years. Pathology of non-weak limb muscles biopsied twice was consistent with active inflammatory myopathy. The ragged-red or cytochrome c oxidase-negative fibers, which are a hallmark of mitochondrial myopathy with PEO, were not increased in comparison with age-matched control muscles. Analysis of mitochondrial DNA in muscle by the Southern blot method did not reveal any deletions. It was concluded that the inflammatory myopathy, myositis clinically localized at the ocular muscles, is an important and distinct disorder in PEO.
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PMID:Progressive external ophthalmoplegia and myositis. 835 24

We describe a 15-year-old boy with full-blown mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) and chronic progressive external ophthalmoplegia (CPEO). He presented with visual disturbance, hearing impairment, continuous partial epilepsy on the right aspect of the face, and right hemiparesis since the age of 13. Four months later, he experienced another strokelike episode with continuous partial epilepsy on the left hand. Serial computed tomographic scans revealed bilateral parieto-occipital hypodense lesions with gyral enhancement and an additional low-density lesion in the right frontal area 4 months later, respectively. Results of laboratory examinations disclosed lactic acidosis and mitochondrial myopathy with many ragged-red fibers. To identify the defective gene in mitochondrial DNA, a simple molecular test was performed by using restriction endonuclease Apa I. A transition from A to G was found at nucleotide position 3243 of the tRNA(Leu) gene. Interestingly, the patient also had marked external ophthalmoplegia and ptosis commonly found in patients with CPEO. Therefore, we suggest that ophthalmoplegia also occurs in the MELAS syndrome.
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PMID:Ophthalmologic manifestations in MELAS syndrome. 836 52

The levels of mitochondrial electron transport system proteins cytochrome c oxidase (COX) and complex III were measured in muscle fibers of patients with mitochondrial encephalomyopathy using quantitative immunoelectron microscopy. In a patient with Leigh's encephalopathy, immunoreactive COX protein was decreased to 20% of the normal mean value in all muscle fibers examined, while the amount of complex III was within the normal range. In a patient with fatal infantile COX deficiency, the level of COX protein was found to be decreased to 27-40% of the normal value in all muscle fibers examined. In patients with mitochondrial myopathy, encephalopathy, lactic acidosis associated with stroke-like episodes (MELAS) and chronic progressive external ophthalmoplegia (CPEO), COX protein levels were decreased to 20% of normal in muscle fibers lacking COX activity. In normal fibers, however, COX protein levels were also normal. The amount of complex III protein was normal in COX-deficient muscle fibers. In two patients, in situ hybridization was performed for detection of mitochondrial mRNA. Mitochondrial mRNAs were found to be abundant in muscle fibers with decreased COX protein, suggesting a defect at the mitochondrial protein-synthesis level in a COX-deficient muscle fiber.
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PMID:Quantitative evaluation of electron transport system proteins in mitochondrial encephalomyopathy. 838 96

A 27 year old man with intestinal pseudo-obstruction who developed parenteral nutrition induced hyperlipidaemia and who also had ophthalmoplegia and an undifferentiated myopathy is described. Histological examination of biopsy specimens and molecular analysis show that this patient had both familial visceral myopathy and a mitochondrial myopathy, suggesting that a mitochondrial DNA mutation is the molecular lesion in familial visceral myopathy.
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PMID:Familial visceral myopathy associated with a mitochondrial myopathy. 843 86

Kearns-Sayre syndrome (KSS) is a form of mitochondrial myopathy in which specific clinical features, namely progressive external ophthalmoplegia, pigmentary retinal degeneration and onset before age 20 occur. It can also be associated with cardiac conduction defects, neurological and variety of endocrine and metabolic disorders. Recognition of mtDNA deletion as the genetic basis of KSS has confirmed the validity of clinical criteria. The purpose of the report is to describe a 30-year-old woman presenting typical clinical features of KSS. On muscle biopsy ragged red fibres and mitochondrial abnormalities on electron microscopy were seen. In spite of menstrual disturbances she became pregnant and delivered health child. In 30 week of pregnancy the VVI pacemaker was implanted because of syncope most probably related to paroxysmal complete heart block.
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PMID:[Complete heart block treated with electrotherapy in a 30-year-old pregnant women with Kearns-Sayre syndrome]. 859 65


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