Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0013421 (dystonia)
 8,418 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Primary torsion dystonia (PTD) is a clinically and genetically heterogeneous group of movement disorders, usually inherited in an autosomal dominant manner with reduced (30-40%) penetrance. The DYT1 gene on chromosome 9q34 is responsible for most cases of early limb-onset PTD. DYT1-PTD clinical spectrum is broad, as the disease may present with several degrees of body involvement and severity. We identified an Italian family with 4 members definitely affected by PTD, genetically diagnosed as carriers of the GAG mutation at DYT1 gene. Phenotype was homogeneous when considering the presentation at onset (limb involvement and early onset), the disease progression was variable; in the subjects of the last generation, the disease progressed to a severe, generalized PTD; in the remaining 2 subjects, dystonia presented with writer's cramp or upper body segmental dystonia of mild severity. One family member, carrier of the GAG mutation on DYT1 gene and mother of the most severely affected individual, presented with a clinically established psychogenic movement disorder resembling dystonia initially diagnosed as a severe generalized PTD. Psychogenic movement disorders are among the most controversial and challenging diseases to diagnose, in particular when the affected individual belongs to a family with an inherited movement disorder.
 ...
PMID:Phenotypic variability of DYT1-PTD: does the clinical spectrum include psychogenic dystonia? 1236 May 59

Myoclonus-dystonia has recently been associated with mutations in the epsilon-sarcoglycan gene (SCGE) on 7q21. Previously, the authors reported a patient with myoclonus-dystonia and an 18-bp deletion in the DYT1 gene on 9q34. The authors have now re-evaluated the patient harboring this deletion for mutations in the SGCE gene and identified a missense change. In the current study, the authors describe the clinical details of this family carrying mutations in two different dystonia genes. Further analysis of these mutations separately and together in cell culture and in animal models should clarify their functional consequences.
 ...
PMID:Clinical findings of a myoclonus-dystonia family with two distinct mutations. 1239 38

Myoclonus-dystonia is a movement disorder associated with mutations in the epsilon-sarcoglycan gene (SGCE) in most families and in the DRD2 and DYT1 genes in two single families. In both of the latter families, we also found a mutation of SGCE. The molecular mechanisms through which the detected mutations may contribute to myoclonus-dystonia remain to be determined.
 ...
PMID:Epsilon-sarcoglycan mutations found in combination with other dystonia gene mutations. 1240 71

The DYT1 dystonia mutation is associated with an abnormal metabolic brain network characterized by hypermetabolism of the basal ganglia, supplementary motor area, and the cerebellum. In this study, we quantified the activity of this network in carriers of other dystonia mutations to determine whether this functional abnormality is linked to genotype. The findings suggest that the DYT1 metabolic topography is not genotype specific and may be present in carriers of other dystonia mutations.
 ...
PMID:Primary dystonia: is abnormal functional brain architecture linked to genotype? 1244 44

Family studies of primary torsion dystonia have used the diagnostic categories of definite, probable, and possible dystonia for gene mapping and identification, but the validity of this hierarchical classification is not known. The authors assessed 147 DYT1 GAG deletion carriers and 113 blood-related noncarriers from 43 families. Only the category of definite dystonia was 100% specific. Probable dystonia, but not possible, was increased in carriers compared with noncarriers. The authors recommend that only those with definite signs of dystonia be considered affected in linkage and other genetic studies.
 ...
PMID:Diagnostic criteria for dystonia in DYT1 families. 1247 70

Torsion dystonia is an autosomal dominant movement disorder characterized by involuntary, repetitive muscle contractions and twisted postures. The most severe early-onset form of dystonia has been linked to mutations in the human DYT1 (TOR1A) gene encoding a protein termed torsinA. While causative genetic alterations have been identified, the function of torsin proteins and the molecular mechanism underlying dystonia remain unknown. Phylogenetic analysis of the torsin protein family indicates these proteins share distant sequence similarity with the large and diverse family of AAA+ proteins. We have established the nematode, Caenorhabditis elegans, as a model system for examining torsin activity. Using an in vivo assay for polyglutamine repeat-induced protein aggregation in living animals, we have determined that ectopic overexpression of both human and C. elegans torsin proteins results in a dramatic reduction of polyglutamine-dependent protein aggregation in a manner similar to that previously reported for molecular chaperones. The suppressive effects of torsin overexpression persisted as animals aged, whereas a mutant nematode torsin protein was incapable of ameliorating aggregate formation. Antibody staining of transgenic animals indicated that both the C. elegans torsin-related protein TOR-2 and ubiquitin were localized to sites of protein aggregation. These data represent the first functional evidence of a role for torsins in effectively managing protein folding and suggest that possible breakdown in a neuroprotective mechanism that is, in part, mediated by torsins may be responsible for the neuronal dysfunction associated with dystonia.
 ...
PMID:Suppression of polyglutamine-induced protein aggregation in Caenorhabditis elegans by torsin proteins. 1255 84

Familial, early onset, generalized torsion dystonia is the most common and severe primary dystonia. Most cases are caused by a 3-bp deletion (GAG) in the coding region of the TOR1A (DYT1) gene, which is widely expressed in human brain and encodes the protein torsinA. This study compares neuropathology and torsinA expression in the normal human brain with that in dystonia cases with and without the GAG deletion. TorsinA-like protein was expressed in neuronal cytoplasm throughout the human brain, including cerebellum, substantia nigra, hippocampus, and neostriatum, with higher levels in specific neurons. This immunostaining pattern was not discernibly different in dystonia and normal brains in midbrain and neostriatal regions. However, nigral dopaminergic neurons appeared to be larger in both GAG-deletion and non-GAG-deletion dystonia brains compared to normal, and may be more closely spaced in GAG-deletion brains. Beyond these apparent changes in neuronal size and spacing in dystonia brains, there was no indication of neuron loss, inflammation, DNA strand breaks, or altered distribution of torsin-like immunoreactivity, supporting a functional rather than degenerative etiology of early onset torsion dystonia.
 ...
PMID:TorsinA protein and neuropathology in early onset generalized dystonia with GAG deletion. 1260 85

The renaissance of functional neurosurgery in the treatment of Parkinson's disease has sparked also the interest in other movement disorders which are refractory to medical treatment. Deep brain stimulation (DBS) has been used only since a few years in dystonia patients. This review summarizes the available data on pallidal and thalamic DBS for various dystonic syndromes. The major advantage of DBS as compared to radiofrequency lesioning is that it allows performing contemporaneous bilateral surgery with relatively low morbidity in these patients. The posteroventral lateral globus pallidus internus (GPi) has been the preferred target in most instances, thus far. While phasic dystonic movements may improve early after surgery, the response of tonic dystonic movements to chronic stimulation may be delayed. The most beneficial results have been achieved in patients with primary genetic generalized and segmental dystonia, myoclonic dystonia, and complex cervical dystonia. Outcome has been varied in patients with other dystonic disorders, in particular those with secondary dystonia. Most studies have reported on relatively short follow-up periods, on single cases, or were retrospective. Pallidal DBS has been shown to be effective in complex cervical dystonia yielding both symptomatic and functional benefit for up to 2.5 years of follow-up. Dramatic improvement has been obtained in children and in adults with DYT1 positive dystonia. Also, patients with non DYT1 genetic dystonia achieved sustained benefit for up to 2 years of follow-up. Preliminary experience indicates that choreoathetosis in patients with cerebral palsy responds less well to pallidal DBS, and that it may not be effective at all in some patients. In single instances unilateral pallidal DBS has been shown to yield valuable benefit in patients with hemidystonia. The experience with DBS for treatment of Meige syndrome and other focal dystonias has been explored only recently. There is much less experience with thalamic DBS for dystonia. Thalamic DBS has been shown to be effective in single cases with posttraumatic dystonia, postanoxic dystonia and paroxysmal nonkinesigenic dystonia. Future perspectives of DBS for treatment of dystonia include the development of new technology, the evaluation of the possible role of other targets, and carefully planned studies to further establish the role of surgery.
 ...
PMID:Deep brain stimulation for dystonia in adults. Overview and developments. 1265 41

Stimulation electrodes are implanted under general anesthesia, without intra-operative electrophysiology or clinical testing, based only on stereotactic MRI and direct anatomical localization of the postero-ventro-basal GPi. We retrospectively analyzed the surgical procedure that has been designed and implemented in our center, using the Leksell G frame, for initiating deep brain stimulation in 65 dystonic patients. We report the surgical technique and the hardware and software complications. We recommend immediate postoperative stereotactic MRI under general anesthesia as a prerequisite to check the reliability of MR acquisition (magnet stability) and the exact localization of each electrode. This technique allowed us to reduce the duration of the operation to 4 h, including general anesthesia, frame fixation, MRI acquisition, implantation of two electrodes under radioscopic control, immediate postoperative stereotactic MRI and frame removal. Surgery-related morbidity was very low with a 0% hemorrhage rate and three delayed unilateral infections re-operated 6 months later. Hardware and software complications were rare. The advances in 3D-MR imaging permit the electrode implantation for deep brain stimulation without resorting to intraoperative localization techniques, which is especially helpful in children and for treating dystonia. The maximum follow-up period is 58 months (first case: November 1996). GPi stimulation has proven to be an effective treatment for most dystonic syndromes with particular efficacy in the disease due to the DYT1 mutation.
 ...
PMID:Deep brain stimulation for dystonia. Surgical technique. 1265 42

Early-onset primary dystonia is an inherited disorder characterized by involuntary twisting, repetitive movements and abnormal postures. It has recently been demonstrated that the DYT1 gene is the most relevant gene associated with primary generalized dystonia. The DYT1 gene product is a 332-aminoacid long protein, termed TorsinA, whose function is still not clear. Based on the results obtained in other species, we proposed that TorsinA, similarly to OOC-5 in nematodes, directs and/or stabilizes the subcellular localization of specific kinases, which may in turn phosphorylate microtubule associated proteins, such as tau. In this way, TorsinA may contribute to maintaining the appropriate site-directed polarization and control neurite outgrowth.
 ...
PMID:TorsinA, microtubules and cell polarity. 1276 Apr 8


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>