Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027066 (myoclonus)
 4,275 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The clinical features and neuropathological findings of two patients suffering from progressive multifocal leukoencephalopathy (PML) are reported. These patients had cancer and died two months and one month after onset of their neurological symptoms, respectively. In both demyelination was discovered only as a result of autopsy due to different reasons: the CAT-scan findings were misinterpreted in the first patient, while in the second diagnosis was overshadowed by the sudden progress towards a fatal outcome preceded by myoclonus and other encephalitis-like manifestations. The major findings were the extreme paucity of the mesodermal elements on the one hand, and the modest spread of the affected areas on the other. It is pointed out that, whatever the size of the lesions, characters were the same and that their formation could hardly be traced in time. The intriguing similarities between PML and several types of demyelination obtained experimentally using certain virus strains are remarked.
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PMID:Progressive multifocal leukoencephalopathy (PML): clinical and pathological findings in two short-duration patients. 241 98

Myoclonic epilepsy and ragged-red fibers (MERRF) syndrome is a rare disorder characterized by myoclonus, muscle weakness, cerebellar ataxia, heart conduction block, and dementia. It has been documented that 80-90% of the patients with MERRF syndrome are caused by the A8344G mutation in the tRNA(Lys) gene of mitochondrial DNA (mtDNA). We and other investigators have reported that the mtDNA mutation results in not only inefficient generation of adenosine triphosphate but also increased production of reactive oxygen species (ROS) in cultured cells harboring A8344G mutation of mtDNA. In addition, we found an imbalance in the gene expression of antioxidant enzymes in the skin fibroblasts of MERRF patients. The mRNA, protein, and enzyme activity levels of manganese-superoxide dismutase were increased, but those of Cu,Zn-SOD, catalase, and glutathione peroxidase did not show significant changes. Recently, we showed that the excess ROS could damage voltage-dependent anion channel, prohibitin, Lon protease, and aconitase in the MERRF cells. Moreover, there was a dramatic increase in the gene expression and activity of matrix metalloproteinase 1, which may contribute to the cytoskeleton remodeling involved in the weakness and atrophy of muscle commonly seen in MERRF patients. Taken together, we suggest that mtDNA mutation-elicited oxidative stress, oxidative damage, and altered gene expression are involved in the pathogenesis and progression of MERRF syndrome.
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PMID:Mitochondrial DNA mutation-elicited oxidative stress, oxidative damage, and altered gene expression in cultured cells of patients with MERRF syndrome. 2041 57