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)

The mitochondrial tRNALeu(UUR) A-->G(3243) mutation was identified in 22 unrelated patients. The probands and their relatives were assessed clinically and by quantitative mitochondrial DNA (mtDNA) analysis. While 10 probands had clinical features consistent with the syndrome of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), usually associated with this mutation, 12 probands had other phenotypes including other encephalopathies, chronic progressive external ophthalmoplegia (CPEO), myoclonic epilepsy and ragged red fibres (MERRF), myopathy alone and diabetes and deafness. Histochemical analyses of muscle biopsies showed a higher proportion of cytochrome oxidase (COX) negative fibres, but fewer strongly COX reactive fibres, in patients with CPEO compared with those with MELAS. The proportion of mutant mtDNA present in blood was significantly greater in symptomatic than asymptomatic subjects, and was correlated with age in both. This correlation was not observed in patients with the tRNALys A-->G(8344) mutation. The proportion of mutant mtDNA A-->G(3243) in muscle was always greater than that in blood. Significant correlations between proportion of mutant mtDNA in blood and both age of onset of disease and a clinical severity score were observed. However, the proportion of mutant mtDNA in blood in affected and unaffected cases overlapped, preventing use of the genetic-clinical correlation for prognostic or predictive purposes. The presence of intrafamilial clustering of phenotypes and the imperfect relationship between proportion of mutant mtDNA and the presence or absence of disease suggests that other factors may determine the phenotype. To investigate this possibility further, the tRNALeu(UUR) gene was sequenced in 23 probands and six relatives. In 28 patients the sequence was normal apart from the 3243 mutation, but in members of one family there was a homoplasmic T-->C transition at position 3290 which was not found in 140 controls or 50 other patients with mitochondrial myopathy. The family with this transition had high levels of mutant mtDNA A-->G(3243), with a unique phenotype of predominant skeletal myopathy, suggesting that this second base change in tRNALeu(UUR) may influence the clinical phenotype.
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PMID:The mitochondrial DNA transfer RNALeu(UUR) A-->G(3243) mutation. A clinical and genetic study. 760 89

A comparative histochemical analysis of the prevalence and cytochrome oxidase staining characteristics of ragged-red fibres in limb skeletal muscles was performed in 19 patients spanning four distinct mitochondrial syndromes: chronic progressive external ophthalmoplegia; myoclonus epilepsy with ragged-red fibres; mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes; and pure limb myopathy. The percentage occurrence of non-ragged red but cytochrome oxidase negative fibres was additionally noted. Ragged-red fibres and cytochrome oxidase-negative fibres were generally more prevalent in the chronic progressive external ophthalmoplegia syndrome than in myoclonus epilepsy ragged-red fibres syndrome or mitochondrial myopathy encephalopathy lactic acidosis and stroke-like episodes syndrome. Isolated cytochrome oxidase-negative fibres were a common finding in each phenotypic syndrome except pure limb myopathy and could involve any of the major fibre types non-specifically. Ragged-red fibres were devoid of cytochrome oxidase activity in chronic progressive external ophthalmoplegia, but commonly displayed activity in the other three syndromes providing a clue to syndromal differentiation on a histochemical basis.
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PMID:Contrasting histochemical features of various mitochondrial syndromes. 762 56

Oculopharyngodistal myopathy is characterized by the adult onset of ptosis, external ophthalmoplegia, dysphagia, and distal weakness. Although dysphagia is common, other gastrointestinal involvement has not been described. We report a case with childhood onset who developed chronic intestinal pseudo-obstruction. Other myopathies associated with ophthalmoplegia and intestinal pseudo-obstruction such as mitochondrial cytopathies were excluded. Whether oculopharyngodistal myopathy is a variant of oculopharyngeal muscular dystrophy or a distinct neuromuscular disorder is unknown and requires further study.
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PMID:Childhood-onset oculopharyngodistal myopathy with chronic intestinal pseudo-obstruction. 763 Mar 44

Defects of the mitochondrial respiratory chain are associated with a great variety of clinical disorders. Whilst recognition of these conditions is increasing, the need for sophisticated biochemical and molecular studies has tended to limit both their investigation and diagnosis to a few specialist centres. Using a group of 51 patients with histochemically, biochemically and/or genetically defined respiratory chain defects, we have examined both the clinical heterogeneity of these disorders and how they may be investigated most effectively in non-specialist centres. We evaluated the use of the following routinely available clinical investigations--fasting intermediary metabolites (lactate, pyruvate, ketone bodies, etc.) in blood and cerebrospinal fluid, serum creatine kinase estimation, EMG, EEG, CT, MRI and histological/histochemical muscle biopsy analysis. Our studies show that, in addition to well-recognized syndromes (e.g. chronic progressive external ophthalmoplegia, mitochondrial encephalopathy lactic acidosis and stroke like episodes, and myoclonus epilepsy with ragged red-fibres, a significant number of patients present with non-specific encephalopathic disorders. Furthermore, even within those categories of respiratory chain disease which have been genetically defined, a wide variation of presenting symptoms and signs were found. Where there was initial doubt concerning the diagnosis, the following clinical features were helpful in suggesting respiratory chain disease: ophthalmoplegia; a maternal pattern of inheritance; the presence of myopathy or deafness in association with encephalopathy. Of the clinical investigations we assessed, elevated lactate in blood or cerebrospinal fluid and low density lesions in the basal ganglia were helpful in identifying patients with respiratory chain dysfunction. Histochemical analysis of muscle was, however, the single most useful investigation being diagnostic in patients with chronic progressive external ophthalmoplegia, Kearns-Sayre syndrome and myopathy, and of significant importance in patients presenting primarily with central nervous system disease. The results of our study are used to discuss the most appropriate approach to diagnosis of this group of disorders.
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PMID:Presentation and clinical investigation of mitochondrial respiratory chain disease. A study of 51 patients. 773 77

We report a patient with mitochondrial encephalomyopathy presenting parkinsonism, as well as her brother who had ataxia but not parkinsonism. Both patients had myopathy, deafness, and insulin-dependent diabetes mellitus. The proband was a 55-year-old woman, who has developed progressive difficulty in walking and slowness of movement since 53 years of age, becoming bed-ridden at 55. Neurological examination revealed mental impairment, a masked face, Myerson's sign, vertical supranuclear ophthalmoplegia, and severe sensorineural deafness, hypokinesia, rigidospasticity, and weakness of the extremities. But tremor and cerebellar ataxia were absent. Her 48-year-old brother gradually developed weakness of the lower extremities and drunken gait over a few years. On neurologic examination, vertical supranuclear ophthalmoplegia, moderate sensorineural deafness, and cerebellar ataxia were present, but parkinsonism was absent. Three other siblings were reported to have died in early childhood. Cranial MR imaging showed cerebral atrophy and mild atrophy of the cerebellar vermis as well as mild periventricular hyperintensities in T2-weighted images in both patients. However, no infarcts were seen. Laboratory investigations revealed slightly elevated lactate and pyruvate levels in the proband and elevation of pyruvate in her brother. A biopsy specimen obtained from the quadriceps muscle showed ragged-red fibers with modified Gomori trichrome staining, and a decrease of complex I+III and complex II+III activity in the proband. Mitochondrial DNA (mtDNA) analysis using the polymerase chain reaction and restriction enzyme Apa I showed a point mutation in the tRNA(Leu)(UUR)) gene (an A to G transition at nucleotide 3243) in both patients.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Mitochondrial encephalomyopathy associated with parkinsonism and a point mutation in the mitochondrial tRNA(Leu)(UUR)) gene]. 802 31

Over the past 13 years at VGH-Taipei, five cases were morphologically defined as having mitochondrial disease and clinically presented with syndromes other than chronic progressive external ophthalmoplegia. There were two cases presenting with dementia, extensive and symmetrical intracerebral calcification but no clinical and other laboratory evidence of skeletal muscle affection; one case with MERRF syndrome; one case with congenital myopathy and cardiomyopathy; and one case with prednisolone-responsive and polymyositis-like myopathy. The following comments are made: 1. The inexplicably lower incidence of encephalopathy group might result from inadequate alertness of clinicians. 2. The clinical classification might have some clinical convenience, but, identification of defects at the DAN level and determination of the phenotypic expression with clinical, morphologic and biochemical methods are fundamental for future rational diagnosis and classification of mitochondrial diseases.
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PMID:Mitochondrial disease with encephalopathy or limb girdle myopathy: a report of five cases. 817 14

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

Mitochondrial diseases are uniquely interesting from a genetic point of view because mitochondria contain their own DNA (mtDNA) and are capable of synthesizing a small but vital set of proteins, all of which are components of respiratory chain complexes. Numerous mutations in mtDNA have been described in the past 5 years, and, it is, therefore, important for the clinician to keep in mind both some characteristic clinical presentations and, more importantly, some basic principles of "mitochondrial genetics," including heteroplasmy, the threshold effect, mitotic segregation, and maternal inheritance. The vast majority of mitochondrial proteins are encoded by nuclear DNA (nDNA) and have to be imported from the cytoplasm into mitochondria through a complex translocation machinery, which is also under the control of the nuclear genome. In addition, nDNA encodes several factors that control mtDNA replication, transcription, and translocation. Mitochondrial diseases due to mutations in nDNA are transmitted as mendelian traits and fall into three categories: (1) alterations of mitochondrial proteins; (2) alterations of mitochondrial protein importation; and (3) alterations of intergenomic communication. The first group of disorders can be further classified on the basis of the biochemical area affected, including defects of transport, defects of substrate utilization, defects of the Krebs cycle, defects of oxidation/phosphorylation coupling, and defects of the respiratory chain. The second group includes only few well-documented disorders but will certainly expand in the near future. The third group includes two conditions, an autosomal dominant form of progressive external ophthalmoplegia associated with multiple mtDNA deletions, and a quantitative defect of mtDNA (mtDNA depletion) causing severe infantile myopathy or hepatopathy.
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PMID:Mitochondrial encephalomyopathies. 821 79

We report a 44 year old man who developed external ophthalmoplegia and predominantly respiratory, truncal and bulbar weakness with brisk reflexes, histological evidence of an inflammatory myopathy and a high titre of acetylcholine receptor antibodies, one month after starting hydroxyurea and allopurinol for chronic myeloid leukaemia. The temporal relationship suggests a possible association between this patient's unusual neuromuscular disorder and either the chronic myeloid leukaemia or its treatment.
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PMID:Complex neuromuscular disorder in a patient with chronic myeloid leukaemia. 832

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


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