Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0033377 (prolapse)
 11,717 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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

A 35-year-old woman with features of Kearns-Sayre syndrome consisting of progressive ptosis, ophthalmoparesis, mitochondrial myopathy, and pigmentary retinopathy also had autoimmune polyglandular syndrome type 11 (Addison's disease, autoimmune insulin-dependent diabetes mellitus, Hashimoto's thyroiditis, and primary ovarian failure). There was no history of similarly affected relatives. Analysis of muscle mitochondrial DNA (mtDNA) revealed a 2,532-bp deletion of the type seen in Kearns-Sayre syndrome as well as a heteroplasmic A3243G mutation in the tRNA-Leu(UUR) gene of the type seen in mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS). The patient's blood and her mother's blood harbored the A3243G mutation but not the deletion, and the maternal grandmother's blood had neither mutation. In muscle, the species of mtDNA harboring the deletion was exclusively associated with the species harboring the A3243G mutation, suggesting that the point mutation predisposed to the large-scale deletion. The mtDNA species with both mutations accounted for 88% of total muscle mtDNA. Other and as yet unrecognized point mutations in mtDNA might also be associated with, and possible causally related to, large-scale mtDNA deletions.
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PMID:MELAS- and Kearns-Sayre-type co-mutation [corrected] with myopathy and autoimmune polyendocrinopathy. 865 48

We report the clinical signs and histological findings in nine patients with mitochondrial ocular myopathies. There were four males and five females. Of age ranging from 47 to 82 years. A more often asymetrical ptosis was in all cases of chronic progressive external ophtalmoplegia (CPEO), but muscle weakness in limbs was not usual. The prognosis in this group was good, but ubidecarenone (150 mg/d) used for two cases, did not improve ophtalmoplegia. The serum creatine kinase was normal in eight of nine cases and electromyography showed myopathic changes in three cases. Histoenzymatic analysis of the muscle biopsy and biochemical studies of mitochondria isolated from the muscle sample demonstrated mitochondrial myopathy associated with partial deficiency of complexes I and/or IV of the electron transfer chain. One of seven patients studied had single deletion by Southern blot analysis, in a heteroplasmic state and another an A-->G transition at position 3243 within the mitochondrial tRNA leu (UUR) gene. Chronic progressive external ophtalmoplegia, without large deletion, may have abnormality in other coding regions of mt DNA such as tRNA, rRNA or protein genes.
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PMID:[Chronic progressive external ophthalmoplegia with mitochondrial anomalies. Clinical, histological, biochemical and genetic analysis (9 cases)]. 873 41

The A3243G mutation of mitochondrial DNA (mtDNA) has been shown to be responsible for or associated with mitochondrial myopathy, encephalopathy, lactic acidosis, strokelike episodes (MELAS) syndrome, diabetes mellitus (DM) and several other neuromuscular diseases. We used polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) to identify the A3243G mtDNA mutation and an electron microscope to examine mitochondrial derangement in the muscle biopsies of a 38-year-old man suspected to have MELAS syndrome with DM. We found great variability in the clinical presentation and in the proportion of mtDNA with the A3243G mutation in the matrilineal family members of the patient. The proband had atypical MELAS syndrome, recurrent vascular headache, and DM (MELASDM), and his mother manifested chronic progressive ptosis and DM (CPPDM). Brain magnetic resonance imaging of the proband showed high signal intensity in the left temporoparieto-occipital area on T2 weighted images (T2WI). The blood lactate level ranged from 2.32 to 4.70 mmol/l, and two-hour postprandial glucose ranged from 124 mg/dl to 148 mg/dl. The blood lactate and postprandial glucose of the proband's mother were 3.15 mmol/l and 192 mg/dl, respectively. Electron microscopic examination of a muscle biopsy of the patient showed abnormal mitochondria with decreased density of cristae and membrane degeneration. No ragged-red fibers were detected in muscle upon staining with modified Gomori trichrome. The hair follicles and blood cells of the patient and his mother showed the A3243G mutation in the tRNA(Leu)(UUR) gene. The proportions of the mutant DNA in the hair follicles and blood cells of the proband were 36.8% and 35.2%, respectively, and those of the patient's mother were 28.8% and 13.9%, respectively. We conclude that the A3243G mtDNA mutation may manifest with MELASDM or CPPDM in different matrilineal members of the same family as a result of differences in random segregation of the heteroplasmic A3243G mutant mtDNA in the affected tissues of patients.
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PMID:Phenotypic heterogeneity in a Chinese family with mitochondrial disease and A3243G mutation of mitochondrial DNA. 1064 55

We studied a patient with ptosis, ophthalmoparesis, and exercise intolerance who showed in her muscle biopsy ragged-red fibers and combined defects of the complexes I and IV of the mitochondrial respiratory chain. Molecular analysis revealed a T3273C transition in the mitochondrial DNA tRNA(Leu(UUR)) gene. The mutation was heteroplasmic and very abundant in muscle from the proposita, less abundant in her other tissues studied, and still less abundant in blood from her maternal relatives. Single muscle fiber analysis showed significantly higher levels of mutant genomes in ragged-red fibers than in normal fibers. The T3273C mutation affects a strictly conserved base pair in the anticodon stem and was not found in controls, thus satisfying the accepted criteria for pathogenicity.
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PMID:A new mtDNA mutation in the tRNA(Leu(UUR)) gene associated with ocular myopathy. 1140 20

The protean manifestations of a novel maternally inherited point mutation of the mitochondrial genome are reported. The proband showed isolated, spastic paraparesis. A brother, who had suffered from a multisystem progressive disorder, ultimately died of cardiomyopathy. Another brother is healthy. The proband's mother showed truncal ataxia, dysarthria, severe hearing loss, mental regression, ptosis, ophthalmoparesis, distal cyclones, and diabetes mellitus. A muscle biopsy performed in the proband failed to show the morphological abnormalities typical of mitochondrial disorders; the activities of respiratory chain complexes were normal. However, complex I and IV activities were low in the muscle homogenate of the affected mother and brother. Sequence analysis of mtDNA showed a heteroplasmic mutation of the tRNA(Ile) gene (G4284A). The mutation load was approximately 55%, 80%, and 90% in the muscle mtDNA of the proband, his mother, and his affected brother, respectively. Mutation was undetected in the healthy brother, as well as in 100 control samples. Several cybrid clones containing homoplasmic mutant mtDNA from the proband showed significant reductions of complex IV activity and maximum oxygen consumption rate, compared with homoplasmic wild-type clones derived from the same subject.
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PMID:Novel heteroplasmic mtDNA mutation in a family with heterogeneous clinical presentations. 1178 91

A 21-year-old woman described proximal muscle weakness since early childhood. At age 16, she developed bilateral ptosis, progressive external ophthalmoplegia, and exercise intolerance. She harbored a heteroplasmic G12315A mutation in the mitochondrial DNA tRNA(Leu(CUN)) gene, which disrupts a highly conserved G-C base pair in the TPsiC stem of the molecule. Mutant mitochondrial DNA was 62% of total in muscle and 17% in blood. The mutation was undetectable in blood, urinary sediment, and hair follicles from the patient's mother. This second patient with G12315A and progressive external ophthalmoplegia confirms the pathogenicity of the mutation and helps to define the correlation between genotype and phenotype.
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PMID:Mitochondrial myopathy and ophthalmoplegia in a sporadic patient with the G12315A mutation in mitochondrial DNA. 1239 39

We report herein the case of a 28-year-old man presenting with hyperglycemic chorea-ballism (HCB) in addition to mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). He was admitted to a local hospital due to weight loss, general fatigue and thirst. The patient had diabetes mellitus, with a blood glucose level of 738 mg/dl and HbA1c of 19.8%. Although insulin therapy improved hyperglycemia, he noticed involuntary movements in the right upper and lower limbs, which subsequently extended to the left side. The patient was thus transferred to our hospital. He displayed short stature (154 cm) and emaciation, and a maternal family history of diabetes mellitus was elicited. He had no history of stroke-like episode, headache, vomiting and seizure. Neurological examination revealed low intelligence (IQ 57), mild sensorineural deafness, and chorea-ballism in the extremities and head without ptosis or eye movement disturbance. Brain computed tomography (CT) demonstrated areas of high density, while T1-weighted magnetic resonance imaging (MRI) revealed extreme hyperintensity and T2-weighted MRI showed hyperintensity in bilateral caudate nuclei, putamina and globi pallidus. HCB was diagnosed. In, CSF, lactate level was increased to 43.9 mg/dl (n, 4-16), pyruvate level was 1.65 mg/dl (n, 0.3-0.9) and total protein concentration was 59 mg/dl. Histological examination of a biopsy sample from the biceps brachii muscle demonstrated ragged-red fibers. An A3243G point mutation in the tRNA(Leu(UUR)) gene was detected, indicating the presence of MELAS. Involuntary movements improved on treatment with haloperidol up to 4.5 mg/day. HCB usually appears in elderly individuals, and cases less than 40-years-old are very rare. The mitochondrial dysfunction in MELAS may accelerate development of HCB.
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PMID:[A case of MELAS presenting juvenile-onset hyperglycemic chorea-ballism]. 1611 32

We identified a novel G3283A transition in the mitochondrial DNA tRNA(Leu (UUR)) gene in a patient with ptosis, ophthalmoparesis and hyporeflexia. Muscle biopsy showed cytochrome oxidase positive ragged-red fibers, and defects of complexes I, III and IV of the mitochondrial respiratory chain. The mutation was heteroplasmic in muscle of the proband, being absent in her blood. Ragged-red fibers harbored greater levels of mutant genomes than normal fibers. The G3283A mutation affects a strictly conserved base pair in the TPsiC stem of the gene and was not found in controls, thus satisfying the accepted criteria for pathogenicity.
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PMID:A novel mutation in the mitochondrial DNA tRNA Leu (UUR) gene associated with late-onset ocular myopathy. 1736 46

An extensive range of molecular defects have been identified in the human mitochondrial genome (mtDNA), many associated with well-characterised, progressive neurological syndromes. We describe a patient who presented to a mitochondrial clinic with progressive bilateral ptosis, external opthalmoplegia and increasing difficulty with walking. He had previously been diagnosed with a dominant, demyelinating polyneuropathy due to PMP22 gene duplication and had also developed gout, presenting in acute renal failure, due to an X-linked recessive HPRT gene mutation. Muscle biopsy revealed many COX-deficient fibres which we show contain high levels of a third genetic defect--a novel, mitochondrial tRNA(Leu(CUN)) (MTTL2) gene mutation.
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PMID:Neuromuscular disease presentation with three genetic defects involving two genomes. 1985 45


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