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)

The patient, a 31-year-old married woman, noticed spasticity on walking at the age of 19 accompanied by ataxia, dysarthria and dysphagia. Facial twitching and dystonic movement of extremities have been observed since age 27. A sister of her father showed the similar ataxia and dysarthria, and expired of pneumonia at the age of 45. On admission at the age of 29, neurological examinations revealed nystagmus, marked spasticity with pathological reflexes and clonus, cerebellar ataxia, dysarthria and dysphagia, diffuse muscle wasting, fasciculation in facial musculature, and generalized slow dystonic movement. By neuro-otological studies bilateral MLF syndrome with upward gaze limitation and decreased velocity of saccadic eye movement were detected. Surface EMG at rest showed a dystonic discharges on the extremities. Needle EMG disclosed a systemic neurogenic change with reduced interference and high amplitude potentials. Atrophy of the brainstem was remarkable on the cranial CT and MRI. These abnormal eye movements, especially bilateral MLF syndrome and generalized dystonia seem to be quite unusual in the variety of spinocerebellar degenerations. On reviewing detected clinical descriptions on Joseph disease this case can be probably included.
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PMID:[A case of spinocerebellar degeneration with bilateral MLF syndrome and dystonia]. 274 81

A solution containing S-nitroso-N-acetylpenicillamine (SNAP), a nitric oxide (NO.-releasing compound, was microinjected in doses of 0.25-2 mumol into a lateral ventricle of conscious rats. SNAP produced dose-dependent convulsions similar to those associated with limbic stimulation, such as tonic extension of the hindlimbs and tail, and dystonia of the forepaws. At 2 mumol, SNAP evoked hyperventilation (arterial hypocapnia), arterial hyperglycemia and caused necrotic lesions of periventricular gray (e.g. lateral septal nucleus) and white matter structures. In the caudate nucleus and lateral septal nucleus ipsilateral to injection, SNAP elicited a bipolar metabolic pattern of low glucose metabolism proximal to the ventricle with higher values occurring more distally. In control studies, we proved that the residue of SNAP decomposition, N-acetylpenicillamine disulfide injected intraventricularly (2 mumol), was without physiological, behavioral, or histological effects. Ventricular pretreatment with methylene blue (2 nmol), a putative inhibitor of guanylate cyclase and superoxide generator, suppressed several of the behavioral manifestations of 1 mumol SNAP, such as the forepaw dystonia, squinting, and facial clonus, but was ineffective on the physiological and histological variables affected by the 2 mumol SNAP dose. Another NO. donor, sodium nitroprusside (2 mumol), produced fewer behavioral and cytotoxic effects over a 55-min observation period, but caused more intense and widely distributed metabolic stimulation, especially in commissural and projection white matter tracts. The results are the basis for a conscious rat model using intraventricular injection of nitrocompounds to examine the physiological, behavioral, metabolic and cytotoxic properties of NO. in the brain.
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PMID:Neurotoxicity in conscious rats following intraventricular SNAP, a nitric oxide donor. 796 12

We studied the effects of intrathecal baclofen upon voluntary movements. Eleven patients with spasticity of different etiology and one patient with idiopathic dystonia were studied. Six patients participated in a double-blind trial. Kinematic/dynamic and electromyographic (EMG) patterns were recorded during attempts at single-joint elbow or ankle voluntary movements and isometric contractions. Reflex responses were also recorded. Baclofen suppressed spastic signs in 10 patients: it eliminated clonus and decreased the co-contraction of antagonist and distant muscle groups. Baclofen could induce weakness, particularly in patients with cerebral palsy (CP). Patients with hemi-syndromes did not notice any effects of baclofen in their 'unaffected' limbs. Intrathecal baclofen could improve voluntary movements in some patients with spasticity resulting in better walking and usage of arms. We hypothesize that spasticity induces an adaptive reaction at a segmental level that includes an increase in the number and/or affinity of GABA-sensitive receptors.
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PMID:Changes in voluntary motor control induced by intrathecal baclofen in patients with spasticity of different etiology. 923 40

The role of endothelin receptor subtypes, i.e., ET(A) and ET(B) receptors, in the behavioral effects of the intracerebroventricular (ICV) administration of endothelin-1 were examined in conscious rats. ICV administration of endothelin-1 (1-9 pmol/rat) dose dependently produced barrel rolling and other convulsive behaviors including bodily twitching, rigidity, back crawling, fore/hindlimb dystonia, fore/hindlimb clonus, tail extension, and facial clonus. Moreover, a marked increase in spontaneous locomotor activity was observed in animals that were treated with a low dose of endothelin-1 (1 pmol/rat, ICV). Endothelin-1 (9 pmol/rat, ICV)-induced barrel rolling and other convulsive behaviors were completely suppressed by the coadministration of BQ-123 (15 nmol, ICV), a specific endothelin ET(A) receptor antagonist, but not of BQ-788 (15 nmol/rat, ICV), a specific endothelin ET(B) receptor antagonist. In contrast, increased locomotor activity produced by treatment with a low dose of endothelin-1 (1 pmol/rat, ICV) was antagonized by coadministration of BQ-788, but not of BQ123. These results indicate that endothelin-1, which has affinity for both endothelin ET(A) and ET(B) receptors, most likely acts on central ET(A) receptors to evoke barrel rolling and other convulsive behaviors. In addition, activation of central ET(B) receptors may be involved in the increase in spontaneous locomotor activity. These results suggest that brain endothelin receptor subtypes may be involved in the regulation of various physiological functions.
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PMID:Role of endothelin receptor subtypes in the behavioral effects of the intracerebroventricular administration of endothelin-1 in conscious rats. 1049 13

Spasticity is only one of several components of the upper motor neurone (UMN) syndrome, known collectively as the 'positive' phenomena, that are characterized by muscle overactivity. Other components include tendon hyper-reflexia, clonus, the clasp-knife phenomenon, flexor and extensor spasms, a Babinski sign, and spastic dystonia. Spasticity is a form of hypertonia due to hyperexcitable tonic stretch reflexes. It is distinguished from rigidity by its dependence upon the speed of the muscle stretch and by the presence of other positive UMN signs. Hyperactive spinal reflexes mediate most of these positive phenomena, while others are due to disordered control of voluntary movement or abnormal efferent drive. An UMN lesion disturbs the balance of supraspinal inhibitory and excitatory inputs, producing a state of net disinhibition of the spinal reflexes. These include proprioceptive (stretch) and nociceptive (flexor withdrawal and extensor) reflexes. The clinical syndrome resulting from an UMN lesion depends more upon its location and extent, and the time since it occurred, than on the pathology of the lesion. However, the change in spinal reflex excitability cannot simply be due to an imbalance in supraspinal control. The delayed onset after the lesion and the frequent reduction in reflex excitability over time, suggests plasticity in the central nervous system. Knowledge of the electrophysiology and neurochemistry of spinal reflexes, together with the action of antispasticity drugs, helps us to understand the pathophysiology of spasticity.
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PMID:The pathophysiology of spasticity. 1191 43

This paper reviews the main neurological complications of psychiatric drugs, in particular antipsychotics and antidepressants. Extrapyramidal syndromes include acute dystonia, parkinsonism, akathisia, tardive dyskinesia and tardive dystonia. Extrapyramidal symptoms (EPS) are less frequent with atypical than with conventional antipsychotics but remain common in clinical practice partly due to lack of screening by health professionals. Neuroleptic malignant syndrome (NMS) consists of severe muscle rigidity, pyrexia, change in conscious level and autonomic disturbance but partial forms also occur. NMS is particularly associated with the initiation and rapid increase in dose of high-potency antipsychotics but it has been reported with all the atypical antipsychotics and rarely with other drugs including antidepressants. Serotonin toxicity comprises altered mental state (agitation, excitement, confusion), neuromuscular hyperactivity (tremor, clonus, myoclonus, hyper-reflexia) and autonomic hyperactivity and occurs on a spectrum. Severe cases, termed serotonin syndrome, usually follow the co-prescription of drugs that increase serotonergic transmission by different pathways, for example a monoamine oxidase inhibitor (MAOI) and a selective serotonin reuptake inhibitor (SSRI). Most antipsychotics and antidepressants lower the seizure threshold and can cause seizures; the risk is greater with clozapine than with other atypical antipsychotics and greater with tricyclic antidepressants (TCAs) than with SSRIs. In randomised controlled trials in elderly patients with dementia atypical antipsychotics are associated with a higher risk of stroke and death than placebo. Cohort studies suggest that conventional drugs carry at least the same risk. Cessation of treatment with antipsychotics and antidepressants can lead to a wide range of discontinuation symptoms which include movement disorders and other neurological symptoms. Clinicians need to be familiar with strategies to reduce the risk of these adverse events and to manage them when they arise. Their occurrence needs to be balanced against the benefits of psychiatric drugs in terms of efficacy and improved quality of life in a range of disorders.
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PMID:Neurological complications of psychiatric drugs: clinical features and management. 1809 17

Clinical lateralizing signs are the phenomena which can unequivocally refer to the hemispheric onset of epileptic seizures. They can improve the localization of epileptogenic zone during presurgical evaluation, moreover, their presence can predict a success of surgical treatment. Primary sensory phenomena such as visual aura in one half of the field of vision or unilateral ictal somatosensory sensation always appear on the contralateral to the focus. Periictal unilateral headache, although it is an infrequent symptom, is usually an ipsilateral sign. Primary motor phenomena like epileptic clonic, tonic movements, the version of head ubiquitously appear contralateral to the epileptogenic zone. Very useful lateralization sign is the ictal hand-dystonia which lateralizes to the contralateral hemisphere in nearly 100%. The last clonus of the secondarily generalized tonic-clonic seizure lateralizes to the ipsilateral hemisphere in 85%. The fast component of ictal nystagmus appears in nearly 100% on the contralateral side of the epileptic focus. Vegetative symptoms during seizures arising from temporal lobe such as spitting, nausea, vomiting, urinary urge are typical for seizures originating from non-dominant (right) hemisphere. Ictal pallor and cold shivers are dominant hemispheric lateralization signs. Postictal unilateral nose wiping refers to the ipsilateral hemispheric focus compared to the wiping hand. Ictal or postictal aphasia refers to seizure arising from dominant hemisphere. Intelligable speech during complex partial seizures appears in non-dominant seizures. Automatism with preserved consciousness refers to the seizures of non-dominant temporal lobe.
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PMID:[Brain lateralization and seizure semiology: ictal clinical lateralizing signs]. 1876 78

Intrathecal baclofen (ITB) is increasingly being used to reduce spasticity among children with cerebral palsy, dystonia, and spinal cord injuries. However, complications such as withdrawal, which is a potentially life-threatening condition, can occur. Intrathecal baclofen withdrawal should be differentiated with autonomic dysreflexia, malignant hyperthermia, neuroleptic malignant syndrome, and serotonin syndrome. We report a case of ITB withdrawal secondary to low residual volume in the pump reservoir and resembling serotonin syndrome in an adolescent with cerebral palsy. He presented with agitation, diaphoresis, increasing spasticity, rigidity, jitteriness, hyperreflexia, clonus, tachycardia, hypertension, and rhabdomyolysis. Treatment consisted of emergent refilling of the pump, intravenous diazepam, and oral cyproheptadine. We also emphasize the importance of prompt recognition of ITB withdrawal among high-risk patients.
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PMID:Intrathecal baclofen withdrawal resembling serotonin syndrome in an adolescent boy with cerebral palsy. 1924 Jun 73

Among the three main factors of motor impairment that emerge in chronological order following a lesion to central motor pathways, the last two antagonize movement: 1) stretch-sensitive paresis, a reduction of agonist motor unit recruitment upon voluntary command, worsened by antagonist stretch; 2) soft tissue contracture, and 3) muscle overactivity. Types of muscle overactivity include 1) spasticity, an increase in the velocity-dependent response to muscle stretch, measured at rest; 2) spastic dystonia, i.e., chronic tonic muscle activity at rest, sensitive to stretch of the dystonic muscle and 3) spastic co-contraction, an inappropriate degree of antagonistic contraction during voluntary agonist command, sensitive to stretch of the co-contracting muscle. A five-step clinical assessment may closely parallel this phenomenology, in which the first four steps aim at quantifying the antagonistic potential of each muscle group. Step-1 measures passive range of motion, i.e., the angle of arrest upon slow stretch of the muscle group assessed (minimizing spastic dystonia), which provides insight on soft tissue length and extensibility. Step-2 measures the angle of catch or clonus upon fast passive stretch of the muscle group assessed, which provides insight on stretch reflex excitability. Step-3 measures the range of active motion against the muscle group assessed, a net result of agonist recruitment minus the combined resistance from passive soft tissue stiffness and spastic co-contraction in the muscle group assessed. Step-4 measures the maximal frequency of rapid alternating movements along the maximal active range of motion, evaluating Step-3 performance repeatability. Step-5 evaluates active function, using for example a walking test (10 m or 2 min) for lower limb and the Modified Frenchay Scale for upper limb assessment, and perceived function through patient global subjective assessment.
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PMID:Five-step clinical assessment in spastic paresis. 2092 7

Spasticity is common in many neurological disorders, such as stroke and multiple sclerosis. It is part of the upper motor neurone syndrome manifesting as increased tone, clonus, spasms, spastic dystonia and co-contractions. The impact of spasticity varies from it being a subtle neurological sign to severe spasticity causing pain and contractures. Existing spasticity can be worsened by external factors such as constipation, urinary tract infections or pressure ulcers. Its management involves identification and elimination of triggers; neurophysiotherapy; oral medications such as baclofen, tizanidine and dantrolene; focal injection of botulinum toxin, alcohol or phenol, or baclofen delivered intrathecally through a pump; and surgical resection of selected dorsal roots of the spinal cord. This article reviews the current understanding of pathophysiology, clinical features and management of spasticity.
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PMID:Spasticity: pathophysiology, evaluation and management. 2297 59


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