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

Hereditary progressive dystonia with marked diurnal fluctuation or the strictly defined dopa-responsive dystonia (HPD/DRD) is an autosomally dominantly inherited dystonia caused by abnormalities of the gene of the GTP cyclohydrolase I (GCH 1) located on the 14q22. 1-q22.2. The heterozygotic gene abnormality induces partial decrement of tetrahydrobiopterin (BH4) and affects synthesis of tyrosine hydroxylase (TH) rather selectively. The reduction of TH exists at the terminals of the nigrostriatal (NS) dopamine (DA) neuron, predominantly in the ventral area of the striatum and disfacilitates the D1 receptor-striatal direct pathway. This consequently disinhibit the inhibitory efferent pathways and develops postural dystonia via the particular descending pathways to the reticulospinal tract and postural tremor via the ascending pathways to the ventralis lateralis (VL) nucleus of the thalamus. This also inhibits the efferents to the superior colliculus, and affects voluntary saccade but spares that to the pedunculo-pontine nucleus (PPN) preserving locomotive movement clinically. The DA-D2 receptors, the striatal indirect pathways or the efferent connecting to these pathways are not involved in the pathophysiology of HPD/DRD. So parkinsonian plastic rigidity, parkinsonian resting tremor, cogwheel rigidity or levodopa induced dyskinesia are not observed. In some patients, particularly in compound hetereozygotes, there are symptoms suggesting the involvement of serotonergic neurons or those thought to be caused by exaggeration of DA-D2 receptors. Neuropathologically there is no degenerative changes. Clinical laboratory examinations suggest that levels of TH and DA activities are around 20% of the normal values throughout the course of illness. Therefore, the age-dependent clinical course, marked progression in the first one and one half decades, its subsiding in the third decade and almost stationary course from the fourth decade are just the reflection of age-related decremental variation of the TH activities at the terminal of the normal NS-DA neuron. The diurnal fluctuation is also the reflection of circadian oscillation of the TH activities at the terminal. Functional maturation of the striatal indirect pathways in the first one and one half decades and developmental decremental variation of the DA-D2 receptor in the first three decades also reflect in the age-dependent variation of symptoms by modulating the background tone of muscle. The later functional development of the ascending efferents of the basal ganglia to the thalamus, may cause the postural tremor which appears in the second decade and becomes predominant in the fourth decade. Early decrease of TH due to deficiency of BH4 in HPD/DRD also affects the DA-D4 receptor of the tuberoinfundibular DA neuron and cause stagnation of increase of body length in childhood. With normal preservation of the fundamental function of the NS-DA neuron, levodopa, by replacing the DA content at the terminal, alleviates the motor symptoms completely and the effects sustain without any side effects. Levodopa also improves the short body length, if it is administrated before puberty. Up to now 60 mutations have been detected in the GCH 1 gene. The locus of mutation differs among families except for two pare of families with different ethnic background which showed identical mutations. Experimentally, one abnormal heterozygotic gene decreased the production of the enzyme to less than 50%, e.g. some below 20% and others around 30-40%, which clinically as symptomatic patients and asymptomatic carriers, respectively. Other experiments show dominant negative effects which differ among families or the loci of mutation. These might be the background for developing the intra-familial variation, that is, in some there is anticipation, and in the other the symptoms and clinical course are identical or vary in a family without any relation to the generation. (ABSTRACT TRUNCATED)
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PMID:Hereditary progressive dystonia with marked diurnal fluctuation. 1098 64

We assessed the oropharyngeal swallowing ability in 8 patients with Parkinson's disease (PD), 8 patients with progressive supranuclear palsy (PSP), and 10 age-matched healthy controls (CTL) using videofluorography (VF). In VF studies, PD and PSP patients demonstrated food pooling on the tongue, difficulty in bolus formation, and bolus falling into pharynx before swallow. PSP patients had a significantly longer delay in the pharyngeal phase and showed food falling into larynx more often than PD patients (p < 0.05). On measurement of swallowing time periods as proposed by Robbins et al., both patient groups showed significantly longer periods during many swallowing phases (P < 0.05) compared to those in the control group, but there were no significant differences between the PD and PSP groups. However, in PSP patients, the time for "transferring the food bolus from the oral cavity to pharynx" which we defined as a distinct stage was significantly longer (p < 0.05) than that in the PD group. We think that the difference in dysphagia characteristics between the two diseases arises from the variations in pathological changes in PSP, including those in the cerebral cortex, cerebellum, pons and medulla tegmentum in addition to the basal ganglia. Dystonia in the neck muscle also plays a role in dysphagia in PSP patients. Levodopa medication, changing the form of foods and training in rehabilitation techniques such as the chin down posture, supraglottic swallowing and ice-massage of the oral region are probably effective for dysphagia in PD patients. In patients with PSP, there are few research reports about the treatment of dysphagia. However, several dysphagia treatments seem to be useful depending on the abnormal patterns in the VF. Further studies are necessary to establish more effective treatments for dysphagia in PD and PSP.
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PMID:[An assessment of dysphagia using videofluorography in Parkinson's disease and progressive supranuclear palsy]. 1133 86

Laboratory studies and studies of animal models of parkinsonism have produced contradictory evidence, but there is no evidence that LD is toxic to normal substantia nigra in animals. We have studied human subjects longitudinally to address that issue. A cumulative LD dose up to 24 kg was not toxic in one autopsied essential tremor (ET) case. Two other ET patients did not develop parkinsonism on 8.5 kg and 21 kg cumulative LD dose, respectively. One DOPA-responsive dystonia (DRD) case has no evidence of parkinsonism after 29 years and more than 17 kg of LD. A DRD patient who received 3 kg over 11 years had normal SN neuronal complement at autopsy. One patient who has clinical and laboratory evidence of nigral pathology as the basis of parkinsonism when untreated for 18 years had progressive disability. While on LD he has excellent symptomatic benefit and virtual cessation of progression of the disease. Epidemiologic studies indicate that those prescribed LD at an early stage of illness and hence given larger cumulative lifetime doses have longer survival than those in whom LD is started late and who receive smaller total doses. Our observations and the available literature support that levodopa is not toxic to normal or diseased substantia nigra in human beings. Evidence presented here indicates that levodopa has a protective effect on the human substantia nigra neurons.
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PMID:The protective role of levodopa in the human substantia nigra. 1155 92

DOPA responsive dystonia (DRD) and sepiapterin reductase (SR) deficiency are inherited disorders of tetrahydrobiopterin (BH4) metabolism characterized by the signs and symptoms related to monoamine neurotransmitter deficiency. In contrast to classical forms of BH4 deficiency DRD and SR deficiency present without hyperphenylalaninemia and thus cannot be detected by the neonatal screening for phenylketonuria (PKU). While DRD is mostly caused by autosomal dominant mutations in the GTP cyclohydrolase I gene (GCH1), SR deficiency is an autosomal recessive disease. The most important biochemical investigations for the diagnosis of these neurological diseases includes CSF investigations for neurotransmitter metabolites and pterins as well as neopterin and biopterin production in cytokine-stimulated fibroblasts. Discovery of SR deficiency opened new insights into alternative pathways of the cofactor BH4 via carbonyl, aldose, and dihydrofolate reductases. As a consequence of the low dihydrofolate reductase activity in the brain, dihydrobiopterin intermediate accumulates and inhibits tyrosine and tryptophan hydroxylases and uncouples nitric oxide synthase (nNOS), leading to neurotransmitter deficiency and possibly also to neuronal cell death.
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PMID:Tetrahydrobiopterin deficiencies without hyperphenylalaninemia: diagnosis and genetics of dopa-responsive dystonia and sepiapterin reductase deficiency. 1159 14

Opioids have been shown to improve L-Dopa induced dyskinesias in patients with Parkinson's disease. In this pilot trial of five patients with tardive and four patients with idiopathic dystonia we tested the effect of morphinsulfate in a retarded form with a dosage of 20-60 mg per day. A substantial improvement of dystonic movements could be observed in four patients with tardive and one patient with idiopathic dystonia. The effect was only transient in tardive dystonia while pain relief mediated by morphine overlasted the effect on involuntary movements.
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PMID:Morphine in tardive and idiopathic dystonia (short communication). 1171 39

Generalized dystonia is known as a type of movement disorder in which pharmacotherapeutic options are very limited. Deep Brain Stimulation (DBS) is well established for Parkinson's disease (PD) and tremor dominant movement disorders. We report on two cases of generalized dystonia which were successfully treated by chronic high frequency stimulation in the Globus pallidus internus (GPI). Two 26 and 27 years old males suffered from severe torsion dystonia and multisegmental dystonia of the lower limbs. Case 1 is a familiar type of dystonia (DYT1 positive). The onset of symptoms in both cases was at age 7. The complaints were initially treated with orally administered benzodiazepines, anticholinergic drugs, later by baclofen and L-DOPA. However there was no response. Case 2 was a patient with a history of left side dominated dystonia since the age of 8. It was first diagnosed as a psychogenic movement disorder. Prior to surgery he was treated with L-DOPA, anticholinergics, Baclofen without any effect. There was only a limited effect on high doses of diazepam. The patient is DYT1 negative. The target point was on both sides the GPI. Intraoperative computerized tomography (CT) and ventriculography (VG) were used for target setting. Furthermore microrecordings were helpful to ensure the exact electrode position. Surgery was performed under analgosedation. Two weeks after surgery we first observed a relief of symptoms in both cases. A significant reduction in the Burke-Fahn-Marsden-Dystonia Movement Rating Scale was observed at the 6 month follow-up (case 1: 95%, case 2: 80%). In case 1 a slight dystonic movement of the left ankle was the only remaining symptom under stimulation. The medication was continuously reduced. At the 24 month follow-up the effect of stimulation remained unchanged. However high stimulation parameters are required to maintain an optimal effect (mean 3.5 V, 400 microseconds, 145 Hz).
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PMID:Deep brain stimulation of the globus pallidus internus (GPI) for torsion dystonia--a report of two cases. 1197 95

Camptocormia is characterized by pronounced forward flexion of the thoracolumbar spine, which increases while walking and disappears in recumbent position. The clinical spectrum of the described disorders with concomitant camptocormia is heterogenous. It was described for the first time in idiopathic Parkinson's disease in 1999. The pathophysiology of this phenomenon remains unclear but seems to be not related to antiparkinsonian treatment. The authors present the case of a 54 years old woman, with idiopathic Parkinson disease diagnosed 5 years ago. The rapid progression of the disease was associated with good response to Levodopa therapy, although the dose had to be increased up to 1400 mg/d (with peripheral decarboxylase and COMT inhibitor). After 5 years she developed painful spasms of paraspinal muscles which resulted in trunk flexion. The clinical picture resembled the described cases of camptocormia. There was no correlation between the appearance of camptocormia and the regime of levodopa administration (time or dosage). Therefore, one can conclude, that presumably camptocormia is not a form of dystonia of the trunk but, the result of till now unclear other factors (dysfunction in other non-dopaminergic nigrostriatal projections?).
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PMID:[Camptocormia, a rare form of motor system disorders in Parkinson's disease]. 1198 8

Deep Brain Stimulation (DBS, chronic high frequency stimulation) is well established for Parkinson's disease and tremordominant movement disorders. Generalized dystonia is known as a type of movement disorder in which therapeutic options are very limited. A case of generalized dystonia is reported which was successfully treated by DBS in the Globus pallidus internus (GPI). A 26 years old male suffered from severe torsion dystonia of the lower limbs. The onset of symptoms was at age 7. It started with dystonia of the left foot. He very fast developed severe dystonia of the lower limbs. These complaints were initially treated by diazepam, later by baclofen (Lioresal ((R))) p.o em leader There was no L-DOPA response. Because of the rapid progression of the disease a cervical spinal cord stimulator was implanted with a transient success. Due to further progression of the disease the patient became wheelchair bounded and resistant for oral medication. Limited improvement of symptoms was achieved using continuous intrathecal administration of baclofen. Finally the patient was treated with 980 microgram intrathecal Baclofen (Lioresal ((R))) daily and up to 100 mg diazepam. Under these conditions the patient remained wheelchair bounded with severe lower limb dystonia. As an ultima ratio it was decided to treat the patient with stereotactic implantation of two electrodes (Medtronic 3387) and two neurostimulators (Medtronic ITREL ((R))II). The GPI was the bilateral target point. Intraoperative computerized tomography and ventriculography were used for target setting. Furthermore microrecordings were helpful to ensure the exact electrode positioning. Surgery was performed under sedation. Two weeks after surgery first improvement of symptoms was observed. Patient was able to stand with assistance. At the three months follow-up he could walk without assistance. Slight dystonic movement of the left ankle was the only remaining symptom under stimulation. The oral medication has been continuously reduced. After 6 months it was stopped. The intrathecal administered baclofen was diminished to 250 microgram daily. At the 24 months follow-up the effect of stimulation remained unchanged. However high stimulation parameters are required to maintain an optimal effect (3,5 V, 400 microseconds 145 Hz for both sides). Deep Brain Stimulation of the Globus Pallidus internus is an alternative approach for severe cases of generalized dystonia.
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PMID:[Chronic high frequency deep brain stimulation of the globus pallidus internus for torsion dystonia]. 1209 79

Ever since it was demonstrated about twenty years ago by two independent groups (Aziz et al. and Bergman et al.) that the cardinal clinical features of MPTP-induced Parkinson's disease (PD) in non-human primate models can be alleviated by lesions of the subthalamic nucleus (STN), this structure has been the focus of interest for functional neurosurgeons involved in the treatment of PD. Initially lesioning and later chronic high frequency stimulation of the STN has become the standard surgical target of akinetic PD. In this brief report we present our experience with 14 STN lesions (8 unilateral and 3 bilateral) confirmed by post-operative imaging. We found significant improvement in OFF rigidity and in ON tremor following unilateral lesions. The major complications were speech disturbance and L-Dopa resistant limb dystonia. Functional disability scores showed inconsistent reduction. There was insufficient data to comment on the significance of bilateral lesions; however, there was a similar pattern of improvement in tremor and speech disturbance. In addition, there was worsening of gait. We comment on the lower degree of improvement in motor scores in our series compared to the few others in recent literature and stress that even in these studies the UPDRS benefits did not translate directly into functional benefit for the patients.
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PMID:Lesioning the subthalamic nucleus in the treatment of Parkinson's disease. 1237 59

The authors report a kindred in which GTP-CH deficiency resulted in a myoclonus-dystonia syndrome. The proband, a 17-year-old boy, presented with early-onset myoclonus and later, dystonia and bradykinesia. Blood prolactin was increased and CSF homovanillic acid, 5-hydroxyindoleacetic acid, and biopterin were all reduced. L-Dopa/carbidopa administration resulted in clinical improvement. In the paternal branch, the grandfather and three relatives had myoclonus-dystonia and resting or postural tremor of limbs. The authors found a missense mutation in the exon 6 of GCH-1 gene (K224R).
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PMID:Autosomal dominant GTP-CH deficiency presenting as a dopa-responsive myoclonus-dystonia syndrome. 1239 38


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