Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0014547 (focal epilepsy)
 1,627 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The ratio of mtDNA and a nuclear reference gene was estimated by Southern blotting in the skeletal muscle DNA of a 3-year-old girl who suffered from congenital brain damage, focal epilepsy, hepatomegaly, malabsorption syndrome and severe myopathy. The signal ratio of mtDNA versus 18S rDNA was 22% of the mean value obtained from controls. No major deletions or insertions were found and the MERRF, MELAS and NARP mutations were ruled out. Mitochondrial DNA-encoded enzyme activities and mitochondrial respiration were reduced. The analysis of the NAD(P)H and flavoprotein redox states of intact fibres revealed the presence of mitochondrial dysfunction. In tissue sections a moderate elevation of type I and type II fibre diameter variation was detected, aberrant NADH- and succinate dehydrogenase staining and some ragged red fibres. This suggested that a mitochondrial disorder caused by a decrease in the amount of intact wild-type mtDNA was responsible for the severe myopathy.
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PMID:mtDNA depletion and impairment of mitochondrial function in a case of a multisystem disorder including severe myopathy. 970 May 97

During seizure-like events (SLEs), intracellular Ca2+ concentration ([Ca2+]i) increases causing depolarization of the mitochondrial membrane and subsequent intramitochondrial accumulation of Ca2+. Mitochondrial depolarization results in an interruption of oxidative phosphorylation and increase in reactive oxygen species. Calcium activates enzymes of the citrate cycle. A characteristic feature of the low-Mg2+-induced SLEs is that they are transformed to a late activity refractory to anticonvulsant drugs, which may be regarded as a model system of difficult to treat status epilepticus. In contrast, 4-aminopyridine (4-AP)-induced activity rarely evolves to such late activity. The autofluorescence of NAD(P)H was used to monitor changes in cellular energy metabolism in the entorhinal cortex in two in vitro models of focal epilepsy. During repetitive 4-AP-induced SLEs there was a short decrease followed by a long-lasting overshoot of the NAD(P)H signal. This sequence remained unaltered during recurring SLEs. In contrast, during recurrent low-Mg2+-induced SLEs, the brief initial NADH signal reduction was unchanged but the following overshoot of NADH displayed a continuous decrease. This indicates a relative energy failure, which may contribute to the transformation to late activity in the low-Mg2+ model.
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PMID:A relative energy failure is associated with low-Mg2+ but not with 4-aminopyridine induced seizure-like events in entorhinal cortex. 991