OBJECTIVE To report an unusual presentation of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) manifested in late life with a clinical picture of herpes simplex encephalitis. DESIGN Case report. SETTING Clinical neurology department in a tertiary care hospital. CASE DESCRIPTION A 55-year-old woman developed aphasia and delirium during ophthalmic herpes z...

C omplex I is the largest of the mitochondrial respiratory chain enzyme complexes, consisting of at least 46 subunits, seven of which are encoded by mtDNA. Deficiency of complex I is the most common respiratory chain defect, and can be caused by mutations in both nuclear and mtDNA encoded genes. It has a wide range of clinical presentations, from lethal infantile mitochondrial disease to isolat...

Received 31 October 1995 and in final revised form 19 February 1996 Accepted 23 February 1996 Abstract Objective-To verify the phenotype to genotype correlations of mitochondrial DNA (mtDNA) related disorders in an atypical maternally inherited encephalomyopathy. Methods-Neuroradiological, morphological, biochemical, and molecular genetic analyses were performed on the affected members of a ped...

BACKGROUND MELAS syndrome (MIM ID#540000), an acronym for Mitochondrial Encephalopathy, Lactic Acidosis and Stroke-like episodes, is a genetically heterogeneous mitochondrial disorder with protean manifestations and occasional kidney involvement. Interest in the latter is rising due to the identification of cases with predominant kidney involvement and to the hypothesis of a link between mitoch...

Defects in mitochondrial DNA (mtDNA) evoke distinctive responses in the nuclear genome, leading to altered mitochondrial biogenesis. We used C(2)C(12) cells depleted of mtDNA (rho(-) cells) and fibroblasts from a mitochondrial encephalopathy, lactic acidosis, and strokelike episodes (MELAS) patient to examine adaptations of the protein import machinery and transcription factors involved in mito...

OBJECTIVE To determine whether there are common symptoms within different phenotypes of the mitochondrial DNA A3243G mutation. DESIGN A series of 52 adults with mitochondrial encephalomyopathies and their symptomatic relatives were screened for the A3243G mutation using restriction enzyme analysis. In addition to clinical examination, patients with the mutation underwent audiometry. RESULTS...

Mitochondrial dysfunction manifests in many forms during childhood. There is no effective therapy for the condition; hence symptomatic therapy is the only option. The effect of symptomatic therapy are not well known. We present clinical course, diagnosis and effect of current treatments for six children suffering from mitochondrial encephalomyopathy identified by clinical demonstrations, brain ...

Researchers in the field of mitochondrial biology are increasingly unveiling of the complex mechanisms between mitochondrial dysfunction and noncoding RNAs (ncRNAs). However, roles of ncRNAs underlying mitochondrial myopathy remain unexplored. The aim of this study was to elucidate the regulating networks of dysregulated ncRNAs in Mitochondrial myopathy, Encephalopathy, Lactic Acidosis, and Str...

BACKGROUND AND PURPOSE DW-MR spectroscopy can detect the diffusion coefficients of NAA, Cr, PCr, and Cho and can, therefore, provide some useful information. The aims of this study were to probe the mechanisms underlying the pathogenesis of MELAS and to see whether DW-MR spectroscopy is a useful technique for other diseases besides cerebral infarction. MATERIALS AND METHODS Fifteen healthy vo...

The A3243G mutation in the mitochondrial gene for human mitochondrial (mt) tRNA(Leu(UUR)), responsible for decoding of UUR codons, is associated with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS). We previously demonstrated that this mutation causes defects in 5-taurinomethyluridine (taum(5)U) modification at the anticodon first (wobble) position of th...