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)

There is nothing more discouraging than for a patient to be given a specific diagnosis, then to be told that there is nothing that can be done. Physicians are equally disheartened to see exponential progress being made in the understanding of the pathophysiology of a complex disorder but few direct benefits resulting for their patients. Over the past 5 years, molecular genetic research has completely revolutionized the way in which the progressive cerebellar ataxias are classified and diagnosed, but it has yet to produce effective gene-based, neuroprotective, or neurorestorative therapies. The treatment of cerebellar ataxia remains primarily a neurorehabilitation challenge, employing physical, occupational, speech, and swallowing therapy; adaptive equipment; driver safety training; and nutritional counseling. Modest additional gains are seen with the use of medications that can improve imbalance, incoordination, or dysarthria (amantadine, buspirone, acetazolamide); cerebellar tremor (clonazepam, propranolol); and cerebellar or central vestibular nystagmus (gabapentin, baclofen, clonazepam). Many of the progressive cerebellar syndromes have associated features involving other neurologic systems (eg, spasticity, dystonia or rigidity, resting or rubral tremor, chorea, motor unit weakness or fatigue, autonomic dysfunction, peripheral or posterior column sensory loss, neuropathic pain or cramping, double vision, vision and hearing loss, dementia, and bowel, bladder, and sexual dysfunction), which can impede the treatment of the ataxic symptoms or can worsen with the use of certain drugs. Treatment of the associated features themselves may in turn worsen the ataxia either directly (as side effects of medication) or indirectly (eg, relaxation of lower limb spasticity that was acting as a stabilizer for an ataxic gait). Secondary complications of progressive ataxia can include deconditioning or immobility, weight loss or gain, skin breakdown, recurrent pulmonary and urinary tract infections, aspiration, occult respiratory failure, and obstructive sleep apnea, all of which can be life threatening. Depression in the patient and family members is common. Although no cures exist for most of the causes of cerebellar ataxia and there are as yet no proven ways to protect neurons from premature cell death or to restore neuronal populations that have been lost, symptomatic treatment can greatly improve the quality of life of these patients and prevent complications that could hasten death. Supportive interventions should always be offered-- education about the disease itself, genetic counseling, individual and family counseling, referral to support groups and advocacy groups, and guidance to online resources. Misinformation, fear, depression, hopelessness, isolation, and financial and interpersonal stress can often cause more harm to the patient and caregiver than the ataxia itself.
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PMID:Cerebellar Ataxia. 1109 49

Therapy for most people with dystonia is symptomatic, directed at lessening the intensity of the dystonic contractions. For a small minority of patients (eg, those with dopa-responsive dystonia, Wilson's disease, or psychogenic dystonia), specific therapy directed at one of the many causes of dystonia is available. Before initiating treatment, clinicians need to decide if a patient has a form of dystonia amenable to such therapy. The most sensitive and least costly method to diagnose DRD is a therapeutic trial of levodopa. It is, therefore, recommended to treat all those with dystonia beginning in childhood or adolescence with low-dose levodopa. For patients with generalized or segmental signs who do not respond to levodopa, other oral medications, including anticholinergics, baclofen, and benzodiazepines, may provide mild to moderate relief; these medications are often given in combinations. For those with focal dystonia, most having adult-onset disease, botulinum toxin A injections often effectively control contractions. The injections produce transient weakness and need to be repeated, generally every 3 to 5 months. There is growing renewed interest in surgical treatment. Peripheral denervating procedures may be helpful for patients with torticollis who do not obtain adequate benefit with botulinum toxin A. The central procedures of pallidotomy and pallidal stimulation are under study; their place in the treatment of the many dystonia subtypes (eg, limb vs axial, generalized vs focal, primary vs secondary) still needs to be established. There are very few studies evaluating physical and psychological therapies or the impact of diet or lifestyle in dystonia. Most clinicians consider physical therapy, including massage, a potential adjunct to medical therapy, and psychological support and stress reduction may help individuals cope with this chronic and frequently disabling condition.
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PMID:Dystonia. 1109 54

Although occurrence of involuntary movements after thalamic stroke has occasionally been reported, studies using a sufficiently large number of patients and a control population are not available. Between 1995 and 1999, the author prospectively identified 35 patients with post-thalamic stroke delayed-onset involuntary movements, which included all or some degree of dystonia-athetosis-chorea-action tremor, occasionally associated with jerky, myoclonic components. A control group included 58 patients examined by the author during the same period who had lateral thalamic stroke but no involuntary movements. Demography, clinical features and imaging study results were compared. There were no differences in gender, age, risk factors, side of the lesion and follow-up periods. During the acute stage of stroke, the patients who had involuntary movements significantly more often had severe (< or = III/V) hemiparesis (50 versus 20%, P < 0.05) and severe sensory loss (in all modalities, P < 0.01) than the control group. At the time of assessment of involuntary movements, the patients with involuntary movements significantly more often had severe sensory deficit (in all modalities, P < 0.01) and severe limb ataxia (60 versus 5%, P < 0.01) than the control patients, but neither more severe motor dysfunction (7 versus 0%) nor more painful sensory symptoms (57 versus 57%). The patients with involuntary movements had a higher frequency of haemorrhagic (versus ischaemic) stroke (63 versus 31%, P < 0.05). Further analysis showed that dystonia-athetosis-chorea was closely associated with position sensory loss, whereas the tremor/myoclonic movements were related to cerebellar ataxia. Recovery of severe limb weakness seemed to augment the instability of the involuntary movements. Persistent failure of the proprioceptive sensory and cerebellar inputs in addition to successful, but unbalanced, recovery of the motor dysfunction seemed to result in a pathological motor integrative system and consequent involuntary movements in patients with relatively severe lateral-posterior thalamic strokes simultaneously damaging the lemniscal sensory pathway, the cerebellar-rubrothalamic tract and, relatively less severely, the pyramidal tract.
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PMID:Delayed onset mixed involuntary movements after thalamic stroke: clinical, radiological and pathophysiological findings. 1115 57

We report a patient of chorea-acanthocytosis (CA), presenting with dilated cardiomyopathy and myopathy. The patient, 40-year-old male, was seen in our clinic because of progressive gait disturbance. Neurologically, he had chorea, tic, dystonia, diminished tendon reflexes and mild muscular atrophy and weakness. Serum creatine kinase level was elevated to 5.514 IU/l, MRI study showed atrophy of the putamen and caudate nucleus. Peripheral nerve involvement was confirmed pathologically and electrophysiologically. Acanthocytosis was found after repeated blood examinations. Furthermore, he had dilated cardiomyopathy on echocardiogram and cardiac muscle biopsy, and his muscle biopsy taken from gastrocnemius indicated myopathic changes with fiber necrosis. From these clinical and laboratory data, he was suspected to have McLeod syndrome (McS). However, he had normal expression of Kell antigens, and direct sequence of XK gene from genomic DNA sample showed no mutations. Accordingly, he was diagnosed as having CA. As CA shares the similar clinical and laboratory features with McS except Kell antigens, the evaluation of Kell blood system is crucial for differential diagnosis. As seen in our patient, blood sampling should be repeated for identification of acanthocytosis, because the finding is not always clearly present.
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PMID:[A case of chorea-acanthocytosis with dilated cardiomyopathy and myopathy]. 1121 3

For nearly a century, physicians have been aware of a syndrome consisting of a relatively stereotyped presentation, usually in young patients, who complain of fatigue, malaise and effort intolerance, sometimes of trembling and weakness of the lower limbs. This is associated with an excessive tachycardia in the orthostatic position. This syndrome has recently been called idiopathic orthostatic tachycardia. The tilt test has enabled "quantification" of normal responses. Patients complaining of the symptoms described above and which, during the first minutes of orthostatism, increase their heart rates by more than 30 beats per minute or attain a rate of at least 110/min, are considered to be suffering from this syndrome. The physiopathology is not clear but, globally, there seems to be two sub-groups, the first considered to be a partial dysautonomic disorder and the second, the result of hypersensitivity of the beta-receptors. Besides the tilt test, the diagnosis can also be presumed after an excessive tachycardia response to an intravenous infusion of 1 microgram/min of isoprenaline. The treatment of these patients is uncertain as there is no single approach which is always effective. In addition to "simple" but essential advice, a number of drugs may be used although there is no means of predicting the efficacy of the result in a given patient. A major principle should be emphasised: ablation of the sinus node for inappropriate tachycardia may eliminate the only compensatory mechanism of autonomic dystonia and make the patients even more symptomatic than they were.
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PMID:[Idiopathic orthostatic tachycardia. Etiology, diagnosis and treatment]. 1122 22

The human genome contains 10 voltage-gated sodium channel genes, 7 of which are expressed in neurons of the CNS and PNS. The availability of human genome sequences and high-throughput mutation screening methods make it likely that many human disease mutations will be identified in these genes in the near future. Mutations of Scn8a in the mouse demonstrate the broad spectrum of neurological disease that can result from different alleles of the same sodium channel gene. Null mutations of Scn8a produce motor neuron failure, loss of neuromuscular transmission, and lethal paralysis. Less severe mutations result in ataxia, tremor, muscle weakness, and dystonia. The effects of Scn8a mutations on channel properties have been studied in the Xenopus oocyte expression system and in neurons isolated from the mutant mice. The Scn8a mutations provide insight into the mode of inheritance, effect on neuronal sodium currents, and role of modifier genes in sodium channel disease, highlighting the ways in which mouse models of human mutations can be used in the future to understand the pathophysiology of human disease.
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PMID:Sodium channels and neurological disease: insights from Scn8a mutations in the mouse. 1149 24

Dopa-responsive dystonia (DRD) is an autosomal dominant disorder typically presenting as dystonia with diurnal variability. Described is an 8-year-old boy who had had waddling gait, generalized hypotonia, and proximal weakness since early childhood. He responded well to low-dose L-dopa. He had a point mutation of the GTP cyclohydrolase I gene. The patient's father and sister had the same mutation but did not have proximal weakness. GTP cyclohydrolase I deficiency can present with hypotonia and weakness.
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PMID:Atypical presentation of dopa-responsive dystonia: generalized hypotonia and proximal weakness. 1157 50

We have described four patients with slowly progressive aphasia with striatal involvement occurring at different stages in the course of the illness. There were two males and two females, and their ages ranged from 68 to 76 (mean: 72) years. The extrapyramidal signs included tremors, bradykinesia, rigidity, and focal dystonia, and one had weakness resembling stroke. There is a heterogeniety among patients with slowly progressive aphasia and the clinical features correspond to the functional anatomy of the areas involved rather than to the pathology.
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PMID:Slowly progressive aphasia with striatal involvement. 1183 16

THALAMUS: The human thalamus is a nuclear complex located in the diencephalon and comprising of four parts (the hypothalamus, the epythalamus, the ventral thalamus, and the dorsal thalamus). The thalamus is a relay centre subserving both sensory and motor mechanisms. Thalamic nuclei (50-60 nuclei) project to one or a few well-defined cortical areas. Multiple cortical areas receive afferents from a single thalamic nucleus and send back information to different thalamic nuclei. The corticofugal projection provides positive feedback to the "correct" input, while at the same time suppressing irrelevant information. Topographical organisation of the thalamic afferents and efferents is contralateral, and the lateralisation of the thalamic functions affects both sensory and motoric aspects. Symptoms of lesions located in the thalamus are closely related to the function of the areas involved. An infarction or haemorrhage thalamic lesion can develop somatosensory disturbances and/or central pain in the opposite hemibody, analgesic or purely algesic thalamic syndrome characterised by contralateral anaesthesia (or hypaesthesia), contralateral weakness, ataxia and, often, persistent spontaneous pain. BASAL GANGLIA: Basal ganglia form a major centre in the complex extrapyramidal motor system, as opposed to the pyramidal motor system (corticobulbar and corticospinal pathways). Basal ganglia are involved in many neuronal pathways having emotional, motivational, associative and cognitive functions as well. The striatum (caudate nucleus, putamen and nucleus accumbens) receive inputs from all cortical areas and, throughout the thalamus, project principally to frontal lobe areas (prefrontal, premotor and supplementary motor areas) which are concerned with motor planning. These circuits: (i) have an important regulatory influence on cortex, providing information for both automatic and voluntary motor responses to the pyramidal system; (ii) play a role in predicting future events, reinforcing wanted behaviour and suppressing unwanted behaviour, and (iii) are involved in shifting attentional sets and in both high-order processes of movement initiation and spatial working memory. Basal ganglia-thalamo-cortical circuits maintain somatotopic organisation of movement-related neurons throughout the circuit. These circuits reveal functional subdivisions of the oculomotor, prefrontal and cingulate circuits, which play an important role in attention, learning and potentiating behaviour-guiding rules. Involvement of the basal ganglia is related to involuntary and stereotyped movements or paucity of movements without involvement of voluntary motor functions, as in Parkinson's disease, Wilson's disease, progressive supranuclear palsy or Huntington's disease. The symptoms differ with the location of the lesion. The commonest disturbances in basal ganglia lesions are abulia (apathy with loss of initiative and of spontaneous thought and emotional responses) and dystonia, which become manifest as behavioural and motor disturbances, respectively.
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PMID:Functional anatomy of thalamus and basal ganglia. 1219 99

A 43-year-old man was admitted to our hospital due to unstable walking, head tilting to the left and difficulty in extending his arm. He was quite healthy until the age of 20 years, when these symptoms appeared and progressed slowly afterward. Due to his unstable walking, he started to use a wheelchair when he was 39 years old. He had no family history of similar disease. On admission, neurological examination revealed spasmodic torticollis, ataxic speech and marked limb and truncal ataxia. Myoclonic jerky flexion of the forearm was induced when he raised and extended his forearm. He also showed mild hyperreflexia in the lower limbs without pathological reflexes. He had weakness and atrophy of the left supraspinatus, infraspinatus, deltoid and biceps brachii muscles and mild superficial sensory impairment in the left axillary nerve territory due to cervical spondylotic radiculopathy of the left C5 root. MRI of the brain demonstrated severe bilateral atrophy of the cerebellar hemispheres and vermis but minimal atrophy of the cerebrum and brainstem. Because surface electromyography revealed continuous discharge with phasic components in the biceps and wrist flexor muscles on extending the upper limbs, the jerky flexion movement of the forearm was considered to be primarily dystonia. Although no giant SEP was observed, a C-response was detected in the long-loop reflex in response to right median nerve stimulation. Nuclear examinations showed diffuse hypoperfusion and decreased glucose metabolism in the cerebellum. Based on these findings, we hypothesized that cerebellar dysfunction may have induced severe dystonic movement resembling myoclonus. We would like to name this complicated involuntary movement an "arm thrust". This is the first case to be reported of sporadic, chronic, progressive cerebellar ataxia accompanied by severe dystonic movement, especially on stretching the forearms, that mimics myoclonic movement.
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PMID:[A case of cerebellar ataxia showing severe dystonia masquerading as myoclonic jerky movements on arm extension]. 1235 58


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