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)

Although a referral bias may have resulted in a higher proportion of atypical cases and consequently an overestimation of dystonia, asymmetric limb dystonia particularly affecting one arm initially was observed in 92% of all our CBD cases. Predominant leg dystonia is uncommon, and head, neck, or axial dystonia is rare. Dystonia is often associated with myoclonus, rigidity, apraxia, alien hand phenomenon, and sensory cortical signs in the affected limb, and there are no significant differences between the occurrence of these or other features, between patients with or without dystonia. There is no effective treatment for this relentless disorder except for temporary relief of dystonia and pain with local botulinum toxin injections. Further clinicopathologic studies are needed to elucidate the anatomical and physiologic substrates of dystonia in this disorder.
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PMID:Dystonia in corticobasal degeneration. 1062 71

Mutations in the EPM2A gene encoding a dual-specificity phosphatase (laforin) cause an autosomal recessive fatal disorder called Lafora's disease (LD) classically described as an adolescent-onset stimulus-sensitive myoclonus, epilepsy and neurologic deterioration. Here we related mutations in EPM2A with phenotypes of 22 patients (14 families) and identified two subsyndromes: (i) classical LD with adolescent-onset stimulus-sensitive grand mal, absence and myoclonic seizures followed by dementia and neurologic deterioration, and associated mainly with mutations in exon 4 (P = 0.0007); (ii) atypical LD with childhood-onset dyslexia and learning disorder followed by epilepsy and neurologic deterioration, and associated mainly with mutations in exon 1 (P = 0.0015). To understand the two subsyndromes better, we investigated the effect of five missense mutations in the carbohydrate-binding domain (CBD-4; coded by exon 1) and three missense mutations in the dual phosphatase domain (DSPD; coded by exons 3 and 4) on laforin's intracellular localization in HeLa cells. Expression of three mutant proteins (T194I, G279S and Y294N) in DSPD formed ubiquitin-positive cytoplasmic aggregates, suggesting that they were folding mutants set for degradation. In contrast, none of the three CBD-4 mutants showed cytoplasmic clumping. However, CBD-4 mutants W32G and R108C targeted both cytoplasm and nucleus, suggesting that laforin had diminished its usual affinity for polysomes. Our data, thus, represent the first report of a novel childhood syndrome for LD. Our results also provide clues for distinct roles for the CBD-4 and DSP domains of laforin in the etiology of two subsyndromes of LD.
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PMID:Genotype-phenotype correlations for EPM2A mutations in Lafora's progressive myoclonus epilepsy: exon 1 mutations associate with an early-onset cognitive deficit subphenotype. 1201 7

Parkinson's disease is associated with classical Parkinsonian features that respond to dopaminergic therapy. Neuropsychiatric sequelae include dementia, major depression, dysthymia, anxiety disorders, sleep disorders, and sexual disorders. Panic attacks are particularly common. With treatment, visual hallucinations, paranoid delusions, mania, or delirium may evolve. Psychosis is a key factor in nursing home placement, and depression is the most significant predictor of quality of life. Clozapine may be the safest treatment for psychotic features, but more research is needed to establish the efficacy of antidepressant treatments. Dementia with Lewy bodies, the second most common dementia in the elderly, may present in association with systematized delusions, depression, or RBD. Early evidence suggests the utility of rivastigmine, donepezil, low-dose olanzapine, and quetiapine in treating DLB. Parkinson-plus syndromes generally lack a good response to dopaminergic treatment and evidence additional features, including dysautonomia, cerebellar and pontine features, eye signs, and other movement disorders. MSA is associated with dysautonomia and RBD. SND (MSA-P) is associated with frontal cognitive impairments, but dementia, psychosis, and mood disorders have not been strikingly apparent unless additional pathological findings are present. In SDS (MSA-A), impotence is almost ubiquitous; urinary incontinence is frequent; depression is occasional, and sleep apnea should be treated to avoid sudden death during sleep. OPCA neuropsychiatric correlates await further definition. Progressive supranuclear palsy neuropsychiatric features include apathy, subcortical dementia, pathological emotionality, mild depression and anxiety, and lack of appreciable response to donepezil. CBD usually is recognized by early frontal dementia with ideomotor apraxia, often in the right upper extremity, attended later by poorly responsive unilateral Parkinsonism, with additional signs including cortical reflex myoclonus, limb dystonia, alien limb, oculomotor apraxia when asked to look horizontally, depression, personality changes, and, occasionally, Kluver-Bucy syndrome. The neuropsychiatry of FTDP-17 involves apraxia, executive impairment, personality changes, hyperorality, and occasional psychosis. Future research in these Parkinsonian disorders should target the characterization of neuropsychiatric sequelae and their treatment.
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PMID:The neuropsychiatry of Parkinson's disease and related disorders. 1555 Feb 93

Dystonia is considered one of the classical features of corticobasal degeneration and is reported in up to 83% in clinical, not pathologically confirmed, series. Here, we aimed to establish the frequency and the clinical characteristics of dystonia in CBD by reviewing the literature on 404 pathologically proven cases. Further, we aimed to identify the frequency and characteristics of dystonia in all described phenotypes with CBD pathology. Dystonia was present in only 37.5% of the 296 cases with adequate information. The majority of the cases with dystonia presented with a corticobasal syndrome, and dystonia occurred in the first 2 years from disease onset, affecting the upper limb. In cases with dystonia that presented with a "dementia" phenotype, dystonia tended to appear later in the disease course and to more affect the cervical region and the face. With regard to the distribution of the phenotypes, fifty-four percent of 374 cases presented as corticobasal syndrome, 15% as frontotemporal dementia, and 10.7% as progressive supranuclear palsy. Dystonia and myoclonus were present in about half of all cases with corticobasal syndrome, implying that these features may not be as frequent in corticobasal syndrome as are akinetic-rigid syndrome and apraxia (100% and 86.3%, respectively). Dystonia and myoclonus almost co-occurred in our analysis, suggesting a possible association. In conclusion, despite dystonia being an inclusion criterion in all sets of clinical criteria for corticobasal degeneration, this was present in only one third of the pathologically proven cases presented here. More accurate characterization of dystonia in corticobasal degeneration would be of importance for clinical diagnosis and development of treatment strategies.
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PMID:Dystonia in corticobasal degeneration: a review of the literature on 404 pathologically proven cases. 2255 31

Corticobasal syndrome (CBS) is a clinical syndrome presenting with progressive asymmetric bradykinesia, rigidity, and dystonia accompanied by cortical signs, such as apraxia, alien limb phenomena, cortical sensory loss, myoclonus, and mirror movements. CBS is associated with different pathological conditions including FTLD-tau (corticobasal degeneration, CBD; progressive supranuclear palsy, PSP: and Pick disease), FTLD-TDP, Alzheimer disease, Creutzfeldt-Jakob disease, and Parkinson disease/dementia with Lewy bodies. Among these, the most common pathology is CBD. In patients with familial and sporadic FTLD, MAPT, GRN and C9orf72 mutations are the three main causes of the disease, even though the C9orf72 mutation is rare in Japan. Patients with MAPT mutations present with FTLD-tau, and patients with GRN and C9orf72 mutations exhibit FTLD-TDP. FTLD is also associated with VCP, CHMP2B, TARDBP and FUS mutations, but each of these account for <1% of familial FTLD cases. In sporadic cases, the H1c haplotype and the rare p.A152T variant of MAPT are known to be associated with FTLD-tau, and the common genetic variant (rs5848) in the 3'-UTR of GRN is associated with FTLD-TDP. A recent genome-wide association study identified TMEM106B as a potential risk-modifying factor for FTLD-TDP, and STX6, EIF2AK3 and MOBP, for PSP. Despite major advances in genetic studies in recent years, the majority of sporadic CBS cases are genetically unsolved. Further studies are needed to unveil the genetic background of CBS. In this review, we discuss the recent advances related to the genetics of CBS, particularly about the genetics of FTLD.
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PMID:[The genetics of corticobasal syndrome]. 2330 Jan

Creutzfeldt-Jakob disease (CJD) is a prion disease, usually presented with memory loss, ataxia, dementia, myoclonus, involuntary movements and psychiatric problems. D178N-homozygous 129M genotype has been recognized in the diagnosis of fatal familial insomnia (FFI) globally. Here we report a patient presented with progressive left upper limb stiffness, bradykinesia, hypomimia and weight loss (10 kg) initially. She progressed to dementia, dysphasia, dysphonia and be bedridden quickly but did not present insomnia. She was diagnosed with CJD corticobasal subtype carrying a classic D178N-129M mutation of PRNP in FFI. Remarkably, she has a strong family history of neurological degeneration diseases but the other members of this pedigree who do not carry D178N-homozygous 129M mutation in PRNP do not present any CJD or FFI symptoms. We conclude that this patient carrying D178N-homozygous 129M mutation in PRNP should be diagnosed as CJD. Thus, the clinicopathology should be considered as a crucial evidence in diagnosing some cases, but FFI could be evaluated as a differential diagnosis with a unique clinical profile. List of abbreviations AD: Alzheimer disease; ADL: Activities of Daily Living; CBD Cortical basal degeneration; CBS: Corticobasal syndrome; CJD: Creutzfeldt-Jakob disease; DWI: Diffusion-weighted image; EEG: Electroencephalograph, fCJD: familial Creutzfeld-Jakob disease; FFI: Fatal familial insomnia; FLAIR: Fluid-attenuated inversion recovery; MMSE: Mini-mental state examination; MoCA: Montreal Cognitive Assessment; MRI: Magnetic resonance imaging; PD: Parkinson disease; PrP: Prion protein; PSWC: Periodic sharp wave complexes; SWI: Susceptibility-weighted imaging.
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PMID:Corticobasal manifestations of Creutzfeldt-Jakob disease with D178N-homozygous 129M genotype. 3294 18