Biochemical mechanisms and management of choreiform movement disorders.
Explore the source record for details and available documents.
SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Tetrabenazine (Nitoman, Roche) is a synthetic benzoquinolizine derivative which resembles reserpine pharmacologically and depletes dopamine and other monoamines in the central nervous system. Considerable evidence has now been accumulated regarding the physiologic equilibrium which exists between dopamine and acetylcholine in the human striatum and it appears that dopamine excess or dopaminergic receptor supersensitivity are mechanisms operating in hyperkinetic disorders like Huntington's Chorea. The treatment of hyperkinetic disorders by dopamine depleting agents, like tetrabenazine or reserpine, or by dopamine blocking agents, like Haloperidol and Pimozide, has not been tried for more than a decade. We report here our own observations in 15 patients with various hyperkinetic disorders treated with tetrabenazine in doses up to 200 mgm. daily for periods up to 12 months.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
BACKGROUND: A growing number of identified genes increasingly reveal genetic overlaps between neurodevelopmental disorders and combined dystonia syndromes. CASE REPORT: We report a 61-year-old man with a neurodevelopmental disorder, mild ataxic signs and generalized dystonia who had been misdiagnosed with cerebral palsy for 40 years. Whole-exome sequencing identified a novel heterozygous pathogenic frameshift variant in TBL1XR1. DISCUSSION: TBL1XR1 variants are classically associated with Pierpont syndrome and autism spectrum disorder. Although movement disorders have been reported, this case suggests generalized dystonia as a possible additional manifestation. It highlights the value of retrospective genetic phenotyping and next-generation sequencing in adults with long-standing neurodevelopmental diagnoses.
The best known biochemical pathway in the brain is probably the nigrostriatal system. Even so, its relationship to Parkinsonism is incompletely understood. Its relationship to Huntington's chorea and the dyskinetic responses is even less well understood. The significance of this system in other related disorders such as Heterogeneous system degeneration, progressive supranuclear palsy, and striatonigral degeneration is still more speculative. In an effort to elucidate underlying neuropharmacology, trials with levodopa, amantadine, haloperidol, and lithium have been undertaken. This increasing concentration in biochemical mediators reflects changing patterns in neurology where new emphasis on biochemical pathways is replacing in current interest the emphasis previously placed on more traditional neuro-anatomical pathways such as the classical ascending sensory and descending motor tracts.
Biallelic variants of the gene encoding for the zinc-finger protein 142 (ZNF142) have recently been associated with intellectual disability (ID), speech impairment, seizures, and movement disorders in nine individuals from five families. In this study, we obtained phenotype and genotype information of 26 further individuals from 16 families. Among the 27 different ZNF142 variants identified in the total of 35 individuals only four were missense. Missense variants may give a milder phenotype by changing the local structure of ZF motifs as suggested by protein modeling; but this correlation should be validated in larger cohorts and pathogenicity of the missense variants should be investigated with functional studies. Clinical features of the 35 individuals suggest that biallelic ZNF142 variants lead to a syndromic neurodevelopmental disorder with mild to moderate ID, varying degrees of delay in language and gross motor development, early onset seizures, hypotonia, behavioral features, movement disorders, and facial dysmorphism. The differences in symptom frequencies observed in the unpublished individuals compared to those of published, and recognition of previously underemphasized facial features are likely to be due to the small sizes of the previous cohorts, which underlines the importance of larger cohorts for the phenotype descriptions of rare genetic disorders.
BACKGROUND: Resilience factors are crucial in the progression of neurodegenerative diseases. However, it remains unclear whether a genetic predisposition to cognitive reserve influences clinical heterogeneity in the prognosis of Parkinson's disease (PD). OBJECTIVES: The aim is to evaluate the utility of polygenic scores (PGSs) for cognitive reserve proxies, including intelligence (INT), educational attainment (EA), and occupational attainment (OA), in predicting the clinical progression of PD. METHODS: Genetic and clinical data for progression of PD (progression to Hoehn and Yahr stage ≥3, progression to a Montreal Cognitive Assessment score ≤24, and occurrence of psychosis) were obtained from the Accelerating Medicine Partnership Parkinson's Disease database. We conducted multivariate Cox regression analysis, adjusting for relevant covariates, including years of education, variants in APOE, GBA1, LRRK2, and other cognitive reserve-related PGSs. RESULTS: All cognitive reserve-related PGSs significantly reduced the risk of cognitive decline, and EA-PGS (hazard ratio [HR], 0.550; 95% confidence interval [CI], 0.447-0.676; P < 0.001) remained significant after controlling for INT-PGS and OA-PGS. EA-PGS (HR, 0.805; 95% CI, 0.672-0.964; P = 0.019) was significantly associated with better motor prognosis after controlling for other PGSs. OA-PGS was linked to a decreased risk of developing psychosis in PD and remained significant after adjusting for others (HR, 0.784; 95% CI, 0.631-0.975; P = 0.029). CONCLUSIONS: Genetic proxies of cognitive reserve are associated with a reduced risk of cognitive decline, motor progression, and development of psychosis in PD. These findings may enhance our understanding of individual differences in resilience in progression of PD. © 2025 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
Tardive dyskinesia (TD), a movement disorder secondary to neuroleptic medication, is frequently found in psychiatric patients. The authors review reasons why some patients with TD go undetected. In addition, they report on another clinical situation which led to TD going undiagnosed: two cases which developed TD, then incorporated their movement disorder into a delusional system. Their clinicians focused exclusively on their psychosis, missing the underlying neurological disorder. How commonly this occurs in clinical practice is unknown.
Explore the source record for details and available documents.
Cases of extrapyramidal-motoric and psychologic side effects are reported when treatment with antidepressant drugs was performed. They have not been mentioned in the literature before. Hypokinetic disorders of speech and motion, tonic-atonic disturbances, dyskinesia and myoclonic muscle contractions are listed. Besides the latter movement disorders, "dreamy state", episodic amnesia ("ictal" amnesia) and amnestic "black out" as transient memory disorders have been observed.
BACKGROUND: Although pathogenic variants in MECP2 are classically associated with Rett syndrome (RTT), increasing evidence suggests that they can underlie a broader spectrum of neurological phenotypes. Clinical manifestations may vary according to sex, variant type, residual protein function, and pattern of X-chromosome inactivation. METHODS: We describe five unrelated individuals carrying pathogenic MECP2 variants identified through multiplex ligation-dependent probe amplification, chromosomal microarray analysis, and next-generation sequencing. Clinical, neuroradiological, neurophysiological, and molecular findings were retrospectively reviewed. RESULTS: Two unrelated girls carrying large de novo Xq28 deletions encompassing the entire MECP2 locus presented with mild neurodevelopmental impairment and epilepsy, but no developmental regression or classic RTT features. Both girls showed borderline cognitive functioning and normal brain MRI. A 9-year-old boy carrying a maternally inherited MECP2 frameshift variant presented with intellectual disability, autism spectrum disorder, and focal epilepsy, whereas carriers in his family exhibited milder neuropsychiatric manifestations. A 44-year-old man carrying a MECP2 missense variant presented with an early-onset spastic-ataxic syndrome, peripheral neuropathy, and cerebellar dysfunction, while a 16-year-old girl patient carrying a distinct de novo MECP2 missense variant displayed isolated mild motor incoordination and subtle cerebellar signs with preserved cognitive functioning. CONCLUSIONS: Our findings expand the evidence that pathogenic MECP2 variants can produce neurological phenotypes distinct from classic RTT, including mild neurodevelopmental impairment without regression, and predominantly cerebellar or spastic-ataxic manifestations associated with limited cognitive involvement. Allelic heterogeneity seems to correlate with clinical phenotypes, at least in our small cohort. In conjunction with established diagnostic criteria, these observations support testing MECP2 in a selection of atypical neurodevelopmental and movement disorder presentations.
A spectral analysis technique for quantifying dyskinesia in patients with diagnosis of Hungtington's Disease (chorea) (H.D.) is described. Spectral analysis involves computation of the magnitude of abnormal involuntary movements (AIMS) and of their distribution in frequency. It has the advantage of providing an objective measure of such movements. Three H.D. patients under different drug regimens and three age-matched controls have been evaluated and representative time records and power spectra are presented. Analysis established marked differences in the amplitude and shape of the normal and patient spectra. In addition, spectral analysis proved sensitive to differences in drug treatments among patients suggesting its additional use in evaluating the efficacy of therapeutic agents in the treatment of movement disorders.
PURPOSE: Synaptic communication deficits are central to many neurodevelopmental disorders. However, for rare monogenic conditions, these disorders remain poorly defined, with limited understanding of their molecular etiology. A homozygous frameshift variant in the synaptic cell adhesion molecule ELFN1 was reported in a family with 3 affected siblings with epileptic encephalopathy, alongside a missense variant of uncertain significance in a cohort study involving a family with intellectual disability. Therefore, we sought to evaluate the role and mechanism of biallelic ELFN1 variants in disease pathogenesis. METHODS: We describe 8 newly identified individuals from 5 unrelated families, all carrying homozygous ELFN1 variants, including frameshift and in-frame deletions. By integrating data from these cases with clinical details from 6 previously reported individuals, we delineate the phenotypic spectrum associated with ELFN1 variants. RESULTS: Clinical features include varying degrees of developmental delay/intellectual disability, epilepsy, and movement disorders. Molecular investigations reveal that these variants disrupt ELFN1 protein trafficking to the cell surface, resulting in loss of function. Functional modeling in mice and zebrafish demonstrates the role of Elfn1 loss in motor activity abnormalities and seizures. CONCLUSION: Our findings establish ELFN1 deficiency as the cause of a distinct, rare neurodevelopmental disorder, providing a foundation for future investigations into its pathophysiology and therapeutic strategies.
In animal experiments Costall and Naylor (1977) showed that Tiaprid, a benzamide derivative of the orthopamids, inhibits dopamine receptors in the caudate nucleus and putamen but not in the mesolimbic system. Involuntary movements in patients with extrapyramidal movement disorders were reduced by 300 mg daily. Good results were obtained in 56% of 93 patients (25 in this study and 68 from the literature). On the whole the efficacy of Tiaprid seems far better than that of neuroleptics, and side effects are definitely fewer.