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

The explosive RDX (hexogen, cyclonite) is usually used for the production of C-4 explosive. The rare occurrence of accidental and intentional RDX intoxications has been reported during manufacturing process or in wartime. In this article, the authors report 5 cases of accidental oral RDX poisoning. On admission, observed signs and symptoms included repetitive generalized tonic-clonic convulsions, postictal coma, lethargy, confusion, hyperreflexia, postictal amnesia, nausea, vomiting, abdominal tenderness, sinusal tachycardia, dysrhythmia with frequent ventricular premature beats, generalized muscle spasms, and myoclonus. Leukocytosis, mild anemia, methemoglobinemia, elevated levels of blood glucose, serum aspartate transaminase, alanine transaminase, lactic dehydrogenase, creatine phosphokinase, amilase, hypokalemia, metabolic acidosis, proteinuria, glucosuria, and myoglobinuria were also noted. Plasma RDX concentrations were 268 to 969 ng/mL at 3 hours of ingestion. For management, supportive and symptomatic measures were taken. Whole-bowel irrigation might have been an effective therapeutic procedure due to probable slow gastrointestinal absorption of RDX. Three patients who developed severe metabolic acidosis underwent urgent hemodialysis. All patients were discharged 7 to 21 days after admission without any sequelae. Plasma RDX levels were strongly correlated with the clinical and laboratory manifestations. The available toxicological data on this rare accidental poisoning are reviewed in light of the literature.
 ...
PMID:Accidental oral poisoning caused by RDX (cyclonite): a report of 5 cases. 1518 66

We reported a patient with middle-aged onset sialidosis type I. A 52-year-old Japanese man was referred to our hospital because of dysarthria, involuntary movement of his extremities and gait disturbance since the age of 46 years. On admission, neurological examination revealed scanning speech, action myoclonus, cerebellar ataxia and cherry-red spots. Vacuolated lymphocytes were found in peripheral blood. Brain 18F-2-fluoro-2-deoxy-D-glucose positron emission tomography (18F-FDG PET) showed decreased glucose metabolism in the cerebellum. Enzymological analysis using his skin fibroblasts revealed primary deficiency of sialidase activity. Sialidase gene analysis identified compound heterozygotes for base substitusions of 239T-to-C and 649G-to-A, which resulted in amino acid alterations of P80L and V217M, respectively. These mutations have been reported in Japanese sialidosis type II (P80L) and I (V217M). Further studies are required to reveal effects of gene mutations on residual enzyme activities and phenotypes.
 ...
PMID:[A case of middle-aged onset sialidosis type I]. 1547 Oct 91

Familial cortical myoclonic tremor (FCMT) is a rare disorder often leading to a wrong clinical diagnosis of essential tremor. Electrophysiological data are usually considered to allow a correct diagnosis. We describe a FCMT French family with previously unreported clinical features such as sensitivity to glucose deprivation, vibration, repetitive visual patterns, and intense visual or auditory stimulation and contrasts. Electrophysiological studies of the propositus confirm the cortical reflex myoclonus elicited by photic stimulation and the absence of epileptic electroencephalographic discharges. We emphasize that a precise clinical analysis can lead to a correct diagnosis before electrophysiological confirmation. This is also the first-ever report of efficacy of levetiracetam in FCMT.
 ...
PMID:Clinical analysis in familial cortical myoclonic tremor allows differential diagnosis with essential tremor. 1628 Dec 96

Patients with Rasmussen encephalitis (RE) may develop a variety of involuntary movements. We report a 26-year-old woman who presented with a 3-year history of progressive, continuous myoclonus of the left side of the face and left arm as well as left spastic hemiparesis. Magnetic resonance imaging of the brain showed right hemisphere and basal ganglia atrophy, and 24-hour electroencephalogram demonstrated diffuse slowing with random sharp waves in both hemispheres. An 18-fluoro-deoxy-glucose positron emission tomography scan indicated hypometabolism of the right cerebral hemisphere, including basal ganglia and thalamus. We successfully treated her myoclonus with injections of botulinum toxin A into the left zygomaticus muscle.
 ...
PMID:Botulinum toxin treatment of facial myoclonus in suspected Rasmussen encephalitis. 1675 85

Corneal clouding is uncommon in infants and children but when present in this age group, it is often associated with mucopolysaccharidoses or Fabry disease. This report describes the case of an 11-year-old male who demonstrated poor weight gain, short stature, segmental myoclonus, and learning problems from 5 years of age followed by general weakness and extremely poor balance. Corneal clouding was evident as a result of a blurred vision complaint at 9 years of age. Both urine metabolic screening for mucopolysaccharidoses and analysis of lysosomal enzymes displayed negative findings. Clinical conditions worsened, including ptosis, progressive weakness, and positive Gowers' sign. Oral glucose lactate stimulation test was positive, therefore a muscle biopsy was performed at 11 years of age. Light microscopy of muscle biopsy disclosed abundant ragged red fibers; electron microscopy revealed abnormal mitochondria in terms of tubular cristae, concentrated cristae, stacking cristae, and round granular patterns of inclusion bodies in the matrix. Thus mitochondrial disease was diagnosed. We conclude that mitochondrial disease should be added to the list of differential diagnosis of corneal clouding in children, especially in cases with normal urine metabolic screening for mucopolysaccharidoses or when assays of lysosomal enzymes appear normal.
 ...
PMID:Corneal clouding: An infrequent ophthalmic manifestation of mitochondrial disease. 1676 25

In a patient with symptomatic ocular myoclonus, the authors observed the regional cerebral metabolic rate of glucose use (rCMRGlu) before and after successful treatment with clonazepam. Even after the symptoms resolved, the rCMRGlu in the hypertrophic olive increased persistently, whereas that in the inferior cerebellar vermis contralateral to the hypertrophic olive decreased. The inferior cerebellar vermis, belonging to the vestibulocerebellar system, may be associated with the generation of symptomatic ocular myoclonus.
 ...
PMID:Glucose utilization in the inferior cerebellar vermis and ocular myoclonus. 1683 91

Chronic post-hypoxic myoclonus, also known as Lance-Adams syndrome (LAS), is a rare complication of successful cardiopulmanry resuscitation often accompanied by action myoclonus and cerebellar ataxia. It is seen in patients who have undergone a cardiorespiratory arrest, regained consciousness afterwards, and then developed myoclonus days or weeks after the event. Worldwide, 122 cases have been reported in the literature so far, including 1 case of Chinese. Here we report 2 Chinese LAS patients with detailed neuroimagings. Cranial single photon emission computed tomography (SPECT) of patient 1, a 52-year-old woman, showed a mild hypoperfusion in her left temporal lobe, whereas patient 2, a 54-year-old woman, manifested a mild bilateral decrease of glucose metabolism in the frontal lobes and a mild to moderate decrease of the N-acetyl aspartate (NAA) peak in the bilateral hippocampi by cranial [(18)F]-fluorodeoxyglucose positron emission tomographic (PET) scan and cranial magnetic resonance spectroscopy (MRS), respectively. We also review the literature on the neuroimaging, pathogenesis, and treatment of LAS.
 ...
PMID:Lance-Adams syndrome: a report of two cases. 1791 Jan 13

An 18-year-old woman presented with epileptic negative myoclonus (ENM) as her major seizure pattern for 4years. Her seizures were characterized by intermittent postural lapse of the right limbs for a period of hours to 2 days. Ictal electroencephalography (EEG)-electromyography showed a silent period that was time-locked to generalized spike-wave discharges. Video/EEG monitoring demonstrated marked improvement of ENM after oral administration of levetiracetam. Cranial magnetic resonance imaging was normal, but 2-deoxy-2-[(18)F]fluoro-d-glucose positron emission tomography during frequent ENM showed hypometabolism in the left frontoparietal cortex. Technetium-99m-ethyl cysteinate dimer single-photon emission computed tomography revealed hyperperfusion over the left parietal cortex and putamen. Here, we document the short-term effects of levetiracetam in this subject with nearly isolated ENM and the neuroimaging results during ENM. Long-term follow-up is in progress to evaluate the clinical evolution and long-term effects of levetiracetam on ENM.
 ...
PMID:Epileptic negative myoclonus: SPECT, PET, and video/EEG studies and the dramatic effects of levetiracetam. 1943 76

We describe a 64-year-old woman who developed spinal myoclonus around the left scapula after long thoracic nerve injury by mastectomy. Involuntary muscle twitching was semi-rhythmic, and ultrasonography identified contraction of the serratus anterior, teres major, and rhomboid muscles. FDG-PET imaging revealed markedly increased glucose uptake only in the serratus anterior. Lidocaine injection into this muscle resulted in complete cessation of the involuntary movement, and then she was successfully treated with botulinum toxin type A. These findings raise the possibility that the myoclonus was primarily caused by ectopic firing of the injured long thoracic nerve, then spreading to adjacent muscles possibly via a central mechanism mediated by group Ia afferents. The new imaging tools, such as FDG-PET and ultrasonography, were useful to determine the therapeutic target muscle.
 ...
PMID:Spinal myoclonus in the periscapular muscles after mastectomy assessed by FDG-PET. 2039 61

Myoclonus can be classified as physiologic, essential, epileptic, and symptomatic. Animal models of myoclonus include DDT and posthypoxic myoclonus in the rat. 5-Hydrotryptophan, clonazepam, and valproic acid suppress myoclonus induced by posthypoxia. The diagnostic evaluation of myoclonus is complex and involves an extensive work-up including basic electrolytes, glucose, renal and hepatic function tests, paraneoplastic antibodies, drug and toxicology screens, thyroid antibody and function studies, neurophysiology testing, imaging, and tests for malabsorption disorders, assays for enzyme deficiencies, tissue biopsy, copper studies, alpha-fetoprotein, cytogenetic analysis, radiosensitivity DNA synthesis, genetic testing for inherited disorders, and mitochondrial function studies. Treatment of myoclonus is targeted to the underlying disorder. If myoclonus physiology cannot be demonstrated, treatment should be aimed at the common pattern of symptoms. If the diagnosis is not known, treatment could be directed empirically at cortical myoclonus as the most common physiology. In cortical myoclonus, the most effective drugs are sodium valproic acid, clonazepam, levetiracetam, and piracetam. For cortical-subcortical myoclonus, valproic acid is the drug of choice. Here, lamotrigine can be used either alone or in combination with valproic acid. Ethosuximide, levetiracetam, or zonisamide can also be used as adjunct therapy with valproic acid. A ketogenic diet can be considered if everything else fails. Subcortical-nonsegmental myoclonus may respond to clonazepam and deep-brain stimulation. Rituximab, adrenocorticotropic hormone, high-dose dexamethasone pulse, or plasmapheresis have been reported to improve opsoclonus myoclonus syndrome. Reticular reflex myoclonus can be treated with clonazepam, diazepam and 5-hydrotryptophan. For palatal myoclonus, a variety of drugs have been used.
 ...
PMID:Myoclonus. 2149 98


<< Previous 1 2 3 4 Next >>