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)

Motor disorders affecting the orofacial musculature include bruxism, chronic orofacial muscle pain affecting the jaw and neck muscles and the involuntary waking period disorders such as orofacial dyskinesia, oral mandibular dystonia, tremor and others. Research at UCLA has touched these and many other areas. Current results have indicated the usefulness of contingent afferent electrical stimulation of the lip to control bruxism; provided information regarding the fatigue, endurance and recovery faculties of the protrusive jaw muscles; explored the issue of chronic muscle hyperactivity inducing headache pain; and worked with botulin toxin as a method to treat orofacial dystonia and dyskinesia.
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PMID:Oral motor disorders in humans. 768 5

Cervical spinal pain is frequently found in conjunction with idiopathic cervical dystonia (ICD), a focal dystonia characterized by sustained deviation of the head. Since the perception of noxious stimuli has never been studied in ICD, we performed a controlled study to obtain more insight into the psychophysics of dystonia-related muscle pain by evaluating pressure-induced pain levels. In nine ICD patients and five gender- and age-matched asymptomatic control subjects, pain-pressure thresholds (PPTs) were determined in the sternocleidomastoid and upper trapezius muscles, both at resting activity and at maximal voluntary contraction (MVC). The masseter muscles served as non-pathological control regions. To determine the accuracy of PPT values, pain intensity and unpleasantness were rated at threshold on 100-mm visual analogue scales. Four replication measurements were obtained. The data were analyzed by multilevel procedures. For all muscles under investigation, average PPTs of the ICD patients were about two times lower than those of the control subjects (P < 0.001-0.0005) and showed a smaller intra-subject variance. Further, average PPTs at MVC were about two times higher than those at resting activity (P < 0.005). These results provide psychophysical evidence to suggest that, at controlled levels of muscle contraction, the threshold of pain perception is decreased in ICD. In addition, ICD patients seem to be better able to establish their own PPTs than control subjects, which might be due to a different setting of the discriminative aspect of pain in ICD. Surprisingly, lower intensity and unpleasantness scores were found in ICD patients with coinciding painful and deviated sides than in ICD patients for whom the painful side was opposite to the deviated one (P < 0.05). This finding might be of clinical importance for defining functional disability and predicting treatment outcome.
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PMID:Pain perception in idiopathic cervical dystonia (spasmodic torticollis). 895 45

We report a 63-year-old man who presented with amoxapine-induced tardive dystonia. At 49 years of age, he developed depression and was administrated 50 mg amoxapine, 4 mg cloxazoram and 3 mg biperiden per day. The daily dose of amoxapine was gradually increased up to 150 mg at 58 years of age. At 61 years of age and after having been taking amoxapine for twelve years, he noticed a rotating left arm and muscle pain in his left shoulder and arm while walking. At 62 years of age, he stopped taking these three drugs. However, the dystonic movements and pain both continued to get worse. Neurological findings revealed no abnormality except for a dystonic posture and movements in the neck and bilateral arms while sitting, standing and walking. Positron emission tomography with C-11 raclopride revealed a mild decrease in the dopamine D 2 receptor numbers in the bilateral striatum. However, two dopamine agonists, pergolide and bromocriptine, worsened his dystonia. In contrast, the daily administration of 2 mg of trihexyphenidyl, an anti-cholinergic agent, markedly ameliorated the dystonia symptoms. As a result, the long-term co-administration of biperiden, an anti-cholinergic agent, may mask the toxicity of amoxapine, which may induce tardive dystonia.
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PMID:[A case of amoxapine-induced tardive dystonia successfully treated with a low dose anti-cholinergic agent]. 1096 55

Botulinum toxin A (BoNT-A) develops its muscle-relaxing effect by the inhibition of acetylcholine (ACh) release. This toxin is also known to relieve muscular pain in different disorders. Conspicuously, pain in some patients responds earlier and sometimes even better than muscle tension, indicating that the effect of BoNT-A on pain is not only due to inhibition of ACh release. A questionnaire was distributed to 88 patients suffering from cervical dystonia (CD). Thirty-five completed questionnaires could be used for data analysis. After intramuscular injections of BoNT-A, patients with CD experience significant reductions in pain which sometimes occur significantly earlier than the improvements in head posture. In the iris sphincter muscle of the rabbit and in dorsal root ganglion cells (DRG) of the rat, inhibition of the release of substance P by BoNT-A has been shown experimentally, and BoNT-C has been proven to develop endopeptidase activity toward substance P (SP) in vitro. Findings in the current literature and our observations allow the conclusion that alleviation of muscle pain by BoNT-A may also be due to an effect on the release of nociceptive neuropeptides, among which SP seems to have a key function.
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PMID:[Reduction of pain and muscle spasms by botulinum toxin A]. 1132 Aug 66

The EMG interference pattern, built up of single motor unit action potentials, may be analyzed subjectively, or objectively by computer aided, quantitative methods, like counting of zero-crossings, counting of spikes, amplitude measurements, integration of the area under the curve, decomposition techniques, power spectrum analysis and turn/amplitude analysis. Since the shape of the interference pattern of healthy muscles is dependent on age, sex, force, muscle, temperature, fatigue, fitness level, recording site and surrounding tissue, electrode type, sensitivity, filters, sampling frequency and threshold level, all methods of analyzing the IP have to be standardized. Quantitative methods of analyzing the EMG interference pattern may be used for monitoring botulinum toxin therapy of dystonia and spasticity, quantifying spontaneous activity, assessment of chronic muscle pain, neuro-urological and proctological function, and diagnosing neuromuscular disorders. For diagnostic purposes, the methods favored are those that use needle electrodes and do not require measurement or monitoring of muscle force. The most well-evaluated methods are those using turn/amplitude analysis, like the cloud methods and the peak-ratio analysis. Peak-ratio analysis has the advantage that reference limits are easy to obtain and that its utility is well established and confirmed by several investigations. Overall, automatic methods of EMG interference pattern analysis are powerful tools for diagnostic and non-diagnostic purposes.
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PMID:EMG-interference pattern analysis. 1153 94

In the course of treatment of psychiatric patients, it is often necessary to switch antipsychotic medications. In recent years, atypical antipsychotic agents have become the first-line therapeutic interventions for treating psychotic symptoms. Reasons for switching patients from the typical antipsychotics to the atypical agents can include enhanced efficacy against negative symptoms, improvement in cognitive capacity, and reduction of risk of extrapyramidal side effects. The presumed long-term benefits of switching to the new antipsychotic drug should be assessed. Pharmacokinetic and pharmacodynamic properties of antipsychotic agents and drug-drug interactions should be considered during the switch process. Two methods are employed for the switch process: crossover ("crosstitration") and an abrupt switch. With the crossover method, the patient's current medication is tapered over a period of several days to several months to prevent potential withdrawal symptoms, such as nausea, vomiting, insomnia, muscle aches, and diaphoresis. Due to withdrawal symptoms, clozapine is the only atypical agent recommended to proceed with a slow dose taper when switching to another atypical drug. Sudden cessation could also precipitate the emergence of motor symptoms, which can include pseudoparkinsonism, dystonia, akathisia, and dyskinesia. The initiation of the new antipychotic occurs concurrently with the tapering of the previous drug. In an abrupt switch, the previous antipsychotic is discontinued suddenly, independent of its dose, and the new antipsychotic is started on the next day. Both methods have been used in clinical practice and double-blind studies. To date, only two medications have been studied in large multicenter clinical trials. These are olanzapine and ziprasidone. The olanzapine study revealed optimal benefits when the previous agents were gradually withdrawn and olanzapine was initiated at 10 mg/day. The ziprasidone switch study demonstrated both reduced adverse side effects from the previous agents and improvements in clinical efficacy. Additional studies are needed to examine the optimal methods for switching patients from one atypical agent to another atypical antipsychotic.
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PMID:Clinical significance of drug binding, protein binding, and binding displacement drug interactions. 1247 62

Over the past 20 years, there has been increasing interest in the medical problems of performing artists. In this review, the major playing-related disorders seen in instrumental musicians are discussed. Among the 1353 instrumentalists personally evaluated, the major diagnoses included musculoskeletal disorders in 64%, peripheral nerve problems in 20%, and focal dystonia in 8%. Of these instrumentalists, 60% were women, although men were the majority in the group with focal dystonia. The average age at the time of evaluation was 37 years for men and 30 years for women. Among musculoskeletal disorders, regional muscle pain syndromes, particularly of the upper limb, upper trunk, and neck, were most common. Specific entities such as tendinitis and ligament sprain were less common. Frequent peripheral nerve disorders included thoracic outlet syndrome, ulnar neuropathy at the elbow, and carpal tunnel syndrome. Each instrument group showed a characteristic distribution of symptoms and signs that appeared to be directly related to the static and dynamic stresses inherent in the playing of the instrument. Electrodiagnostic studies are an important part of the evaluation of these disorders, particularly nerve entrapment syndromes. With carefully designed treatment, the majority of instrumental musicians can return to full and pain-free playing. Nerve entrapment syndromes have the highest treatment success rate, followed by musculoskeletal pain syndromes. Despite some recent innovative approaches, focal dystonia remains largely resistant to therapy.
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PMID:Neuromuscular and musculoskeletal problems in instrumental musicians. 1270 74

In this prospective study we report the results of EMG-guided BOTOX injections in a total of 15 cervical dystonia (CD) patients. Pre-treatment and post-treatment evaluations included physical examination results, Tsui ratings, and video recording. The dosage of BOTOX injection was determined by the EMG pattern, type of CD, and the degree of muscle hypertrophy. Seven patients underwent injections with and without EMG, and eight patients underwent injections with EMG-guidance only. The results showed that among the patients who underwent EMG-guided BOTOX injection there are: (1) fewer BOTOX-related side effects due to injection of the adequate dose of BOTOX to the accurate site of hyperactive muscles, (2) greater clinical improvement due to confirmation of hyperactivity in muscles in each type of cervical dystonia, (3) a better ability to reduce the amount of oral medication for treatment of muscle pain and spasms. We suggest that the use of EMG-guided BOTOX injections be considered for those CD patients with retrocollis, those who have had a sub-optimal treatment response to non EMG-guided BOTOX injections, and those with increased concern of side effects or a concomitant goal of reducing oral medications.
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PMID:The finding and evaluation of EMG-guided BOTOX injection in cervical dystonia. 1547 78

With the possible introduction of exon skipping therapy in Duchenne muscular dystrophy, it has become increasingly important to know the role of each exon of the dystrophin gene to protein expression, and thus the phenotype. In this report, we present two related men with an unusually mild BMD associated with an exon 26 deletion. The proband, a 23-year-old man, had slightly delayed motor milestones, walking 1 1/2 years old. He had no complaints of muscle weakness, but had muscle pain. Clinical examination revealed no muscle wasting or loss of power, but his CK was 1500-7000 U/l. Muscle biopsy showed dystrophic changes. He had comorbidity with dystonia, slight mental retardation, low stature and neuropathy. The brother of the proband's mother came to medical attention when he was 43 years old. He complained about muscle pain. On examination, a MRC grade 4+ hip extention palsy and a discrete calf hypertrophy was noted. Creatine kinase was normal or raised maximally to 500 U/l. The muscle biopsy was myopathic with increased fiber size variation and many internal nuclei, but no dystrophy. No comorbidity was found. In both cases, western blot showed a reduced dystrophin band. Genetic evaluation revealed a deletion of exon 26 of the dystrophin gene in both. This is the first description of patients with a exon 26 deletion of the dystrophin gene. Assuming the proband's comorbidity is unrelated, exon 26 deletion results in a very mild phenotype. This might be of interest in planning exon skipping therapy for Duchenne muscular dystrophy. This report also shows that BMD may present with a normal CK.
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PMID:Deletion of exon 26 of the dystrophin gene is associated with a mild Becker muscular dystrophy phenotype. 2261

Botulinum toxin (Botox) is an exotoxin produced from Clostridium botulinum. It works by blocking the release of acetylcholine from the cholinergic nerve end plates leading to inactivity of the muscles or glands innervated. Botox is best known for its beneficial role in facial aesthetics but recent literature has highlighted its usage in multiple non-cosmetic medical and surgical conditions. This article reviews the current evidence pertaining to Botox use in the head and neck. A literature review was conducted using The Cochrane Controlled Trials Register, Medline and EMBASE databases limited to English Language articles published from 1980 to 2012. The findings suggest that there is level 1 evidence supporting the efficacy of Botox in the treatment of spasmodic dysphonia, essential voice tremor, headache, cervical dystonia, masticatory myalgia, sialorrhoea, temporomandibular joint disorders, bruxism, blepharospasm, hemifacial spasm and rhinitis. For chronic neck pain there is level 1 evidence to show that Botox is ineffective. Level 2 evidence exists for vocal tics, trigeminal neuralgia, dysphagia and post-laryngectomy oesophageal speech. For stuttering, 'first bite syndrome', facial nerve paresis, Frey's syndrome, oromandibular dystonia and palatal/stapedial myoclonus the evidence is level 4. Thus, the literature highlights a therapeutic role for Botox in a wide range of non-cosmetic conditions pertaining to the head and neck (mainly level 1 evidence). With ongoing research, the spectrum of clinical applications and number of people receiving Botox will no doubt increase. Botox appears to justify its title as 'the poison that heals'.
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PMID:An evidence-based review of botulinum toxin (Botox) applications in non-cosmetic head and neck conditions. 2347 31


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