Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0004134 (ataxia)
 15,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A patient with Friedreich's disease and chronic progressive external ophthalmoplegia is descirbed. An investigation was performed into the nature of the ocular motor disorders, which appeared clinically to be supranuclear. The EMG of the ocular muscles suggested myopathy. A specimen of ocular muscle was obtained by biopsy and examined with the light microscope and-for the first time-under the electron microscope. Signs of mitochondrial myopathy were found alongside neurogenic features. Postmortem examination of the central nervous system confirmed the diagnosis of Friedreich's disease with lesions of the motor cells in the anterior horn of the spinal cord. No evidence was found for a supranuclear or inernuclear origin of the ocular palsies, but 20-30 per cent of the neutrons in the nuclei III and IV were atrophic. Lesions of the non-medullated motor nerve fibres were also visible under the electron microscope. That the origin of the c. p. e. o. in this heredo-ataxia is neurogenic-nuclear is postulated on the grounds of the neuropathological and electronmicroscopic findings. Resemblances to the microscopic and submicroscopic and submicroscopic appearance of many types of "ocular myopathy" and "ophthalmoplegia-plus" throw doubt upon the myogenic character of these conditions. Possibly chronic, slowly progressive atrophy in the nuclear areas of the ocular motor nerves must in these cases also be held responsible for the c. p. e. o. Perhaps Moebius's Kern-Schwund theory may be revived after 85 years.
 ...
PMID:Chronic progressive external ophthalmoplegia in a heredo-ataxia: neurogenic or myogenic? A clinical, neuropathological and submicroscopic study. 60 73

During a six-year period, an adolescent girl developed a polyglandular disease characterized by hypoparathyroidism, chemical diabetes, growth failure and pubertal delay, hypercholesterolemia, and hypomagnesemia. A slowly progressive neurological disorder occurred simultaneously, consisting of progressive external ophthalmoplegia, mitochondrial myopathy, ataxia, neural deafness, mental subnormality, atypical retinitis, corneal dystrophy, cataract, and increased protein level in the cerebrospinal fluid. An intracardiac conduction defect was also found. This disorder, the cause of which is uncertain, is termed oculocraniosomatic disease. Our patient is apparently unique in that there was an associated hypoparathyroidism.
 ...
PMID:Oculocraniosomatic neuromuscular disease with hypoparathyroidism. 84 67

A number of mitochondrial DNA (mtDNA) mutations have been identified which cause familial, late onset neuromuscular degenerative diseases. These include missense mutations in most of the mtDNA polypeptide genes as well as base substitutions in several tRNA genes. Missense mutations in the mitochondrial electron-transport genes cause Leber hereditary optic neuropathy. Ten mutations have been associated with this disease, but four at nps 11,178, 3460, 4160 and 15,257 appear sufficient in themselves to cause the disease. One missense mutation in the ATPase 6 gene at np 8993 causes a second phenotype, neurogenic muscle weakness, ataxia and retinitis pigmentosum. Transfer RNA mutations have been identified for myoclonic epilepsy and ragged-red fibre disease in the tRNA(Lys) gene at np 8344 and for the mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes syndrome and for maternal mitochondrial myopathy and cardiomyopathy syndrome in the tRNA(Leu)(UUR) gene at nps 3234 and 3260, respectively. Deficiencies in mitochondrial oxidative phosphorylation enzymes have been observed in several common neurodegenerative diseases such as Alzheimer and Parkinson diseases. Perhaps mtDNA mutations play a role in these as well.
 ...
PMID:Diseases resulting from mitochondrial DNA point mutations. 152 7

A patient is described who has features of Pearson syndrome and who presented in the neonatal period with a hypoplastic anemia. He later developed hepatic, renal, and exocrine pancreatic dysfunction. At the age of 5 years he developed visual impairment, tremor, ataxia, proximal muscle weakness, external ophthalmoplegia, and a pigmentary retinopathy (Kearns-Sayre syndrome). Muscle biopsy confirmed the diagnosis of mitochondrial myopathy. Analysis of mtDNA from leukocytes and muscle showed mtDNA heteroplasmy in both tissues, with one population of mtDNA deleted by 4.9 kb. The deleted region was bridged by a 13-nucleotide sequence occurring as a direct repeat in normal mtDNA. Both Pearson syndrome and Kearns-Sayre syndrome have been noted to be associated with deletions of mtDNA; they have not previously been described in the same patient. These observations indicate that the two disorders have the same molecular basis; the different phenotypes are probably determined by the initial proportion of deleted mtDNAs and modified by selection against them in different tissues.
 ...
PMID:Pearson syndrome and mitochondrial encephalomyopathy in a patient with a deletion of mtDNA. 198 62

Multiple deletions of the mitochondrial genome were found in a family in which the proband had ataxia and ketoacidotic comas. A progressive multiorgan involvement appeared in the course of the disease, and histopathological investigation demonstrated mitochondrial myopathy features with ragged red fibers. A defect of oxidative phosphorylation was found in both skeletal muscle and lymphocytes. It is surprising that various mtDNA deletions were detected both in the proband and in his healthy mother and maternal aunt but not in the rest of the maternal progeny. All the deletions were located between Cox II and cytochrome b genes, and short (4-5 bp) repeated sequences were consistently present at the boundaries of the rearrangements in different tissues. Therefore, the deletions appear not to be transmitted per se but to be inherited in a Mendelian manner, being possibly dominant. Both the Mendelian inheritance of the trait and the variety of the deletions in carriers suggest that a nuclearly encoded factor(s) might be involved in the triggering of the deletions. However, the presence of the rearrangements in healthy individuals raises the question of whether mtDNA deletions actually cause the clinical expression of the disease.
 ...
PMID:Autosomal dominant deletions of the mitochondrial genome in a case of progressive encephalomyopathy. 201 91

A 12 year old girl with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke like episodes (MELAS) is reported. After a normal childhood, at 9 years of age she developed generalized and hemilateralized seizures. Posteriorly, these episodes became more frequent and were accompanied by headache, homonimous hemianopsia, ataxia, vomiting, photophobia, left hemiparesis, slurred speech and even convulsive status. Laboratory tests evidenced lactic acidosis, brain lucencies at CT Scan and ragged skeletal muscle fibers at muscle biopsy.
 ...
PMID:[Mitochondrial encephalomyopathy, lactic acidosis and features of cerebrovascular disorders]. 207 86

A variable combination of developmental delay, retinitis pigmentosa, dementia, seizures, ataxia, proximal neurogenic muscle weakness, and sensory neuropathy occurred in four members of a family and was maternally transmitted. There was no histochemical evidence of mitochondrial myopathy. Blood and muscle from the patients contained two populations of mitochondrial DNA, one of which had a previously unreported restriction site for AvaI. Sequence analysis showed that this was due to a point mutation at nucleotide 8993, resulting in an amino acid change from a highly conserved leucine to arginine in subunit 6 of mitochondrial H(+)-ATPase. There was some correlation between clinical severity and the amount of mutant mitochondrial DNA in the patients; this was present in only small quantities in the blood of healthy elderly relatives in the same maternal line.
 ...
PMID:A new mitochondrial disease associated with mitochondrial DNA heteroplasmy. 213 62

The authors describe a family (mother, son and two daughters) with mitochondrial myopathy. The mother was asymptomatic. Two daughters had lactic acidosis and myoclonic epilepsy, mild dementia, ataxia, weakness and sensory neuropathy. The son suffered one acute hemiplegic episode due to an ischemic infarct in the right temporal region. All the patients studied had hypertension. EEG disclosed photomyoclonic response in the proband patient. Muscle biopsy disclosed ragged-red fibers and abnormal mitochondria by electron microscopy. Biochemical analysis showed a defect of cytochrome C oxidase in mitochondria isolated from skeletal muscle. Several clinical and genetic aspects of the mitochondrial encephalomyopathies are discussed.
 ...
PMID:Mitochondrial myopathy and myoclonic epilepsy. 216 73

Of 85 consecutive patients with mitochondrial myopathy, 29 had clinically significant central nervous system involvement. Nine of these had movement disorders that included dystonia, chorea, parkinsonism, and myoclonus. Autopsy studies of one patient with ataxia, dementia, and parkinsonism followed by dystonia showed the features of olivopontocerebellar atrophy with additional degenerative changes in the basal ganglia. Postmortem in a further case with myoclonus, deafness, muscle weakness, retinopathy, and ataxia showed symmetrical mineralisation of the striatopallidodentatal system.
 ...
PMID:Movement disorders in mitochondrial myopathies. A study of nine cases with two autopsy studies. 232 72

A 12-year-old boy with corticosteroid-responsive mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) is described. His mother proved to have an asymptomatic mitochondrial myopathy on examination of a muscle biopsy specimen. Three weeks after the onset of vomiting, headache, ataxia and visual and speech impairment, he presented with a background of somatic growth retardation, deafness and school failure. Examination revealed disorientation, dysphasia, dyspraxia, optic atrophy, hemianopia, hemiparesis and sensory inattention. A cranial computed tomographic scan disclosed a large, low-density area, which was consistent with infarction, in the left posterior hemisphere and marked calcification of the basal ganglia bilaterally. Within two weeks of the commencement of corticosteroid treatment, the neurological dysfunction resolved. Attempts to decrease the dosage of dexamethasone caused an exacerbation of symptoms repeatedly. Two weeks after ceasing corticosteroid therapy, the patient developed a serious neurological relapse and a new, large, low-density area, which resembled an infarction, in the right posterior hemisphere on a computed tomographic scan. The reintroduction of corticosteroid therapy again resulted in the rapid resolution of all symptoms. It became evident that the patient had an exquisitely sensitive corticosteroid dependency, whereby a reduction in the dexamethasone dosage of even 0.25 mg a day caused confusion, headaches and increasing lactic acidaemia. Although it is difficult to assess the impact of various therapies in MELAS because of the episodic natural course of the disease, this remarkable corticosteroid responsiveness also has been noted in four previously reported patients with MELAS syndrome; therefore, it would seem reasonable to suggest that corticosteroid therapy now should be considered as standard treatment for this condition. However, corticosteroid therapy in other forms of mitochondrial disorders still awaits careful evaluation.
 ...
PMID:Mitochondrial encephalomyopathy with corticosteroid dependence. 273 98


1 2 3 4 5 Next >>