Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

People can remember the content of a dream in rapid eye movement (REM) sleep but cannot do so in slow-wave sleep. According to a brain model, memory is stored in encoding synapses as presynaptic axonal 'on-off' patterns and modulating synapses help encoding synapses convert short-term memory into long-term memory. These lead to the hypothesis that REM sleep involves modulating synapses of the memory-conversion circuits including the anterior nuclei and dorsomedial nuclei of the thalamus. Cortical neurons get more rest in slow-wave sleep than in REM sleep. The locus coeruleus, raphe nuclei, and tuberomammillary nuclei get more rest during REM sleep when these nuclei cease to fire. The paralyses of peripheral muscles during REM sleep and cataplexy, and cessation of chorea, athetosis, hemiballismus, and parkinsonism tremor during sleep may result from spinal cord inhibition by the gigantocellular nuclei and raphe nuclei at the reticular formation. Sleep and wake relate to the light-dark cycle on the Earth. Were the light-dark cycle 50 hours a day, the human circadian clock might be around 50 hours. With increasing use of artificial light to keep people awake at night, it may affect the circadian rhythm and firing rate of neurons, the presynaptic axonal 'on-off' patterns as content of consciousness, and the mood.
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PMID:Rapid-eye-movement sleep involves the memory-conversion circuits in a brain model. 1105 19

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

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

Myoclonus, defined as shock-like involuntary movement, may be physiological or caused by a very wide variety of hereditary and acquired conditions. Because myoclonus can originate from different disorders and lesions affecting quite varied levels of the central and peripheral nervous systems, it represents from many points of view a diagnostic challenge. Moreover, new entities have been recently individualized, such as cortical tremor, which deserve renewed attention. The aim of this review is to propose a rationale for a diagnostic approach based on clinical and electrophysiological grounds. In this setting, we successively address 1) the clinical features allowing a positive diagnosis of myoclonus; 2) the clinical clues to the etiology; 3) the relevance of the clinical context to the diagnosis; and 4) the contribution of neurophysiology. Differentiating myoclonus from tics, spasm, chorea and dystonia can be difficult, and a careful reappraisal of clinical features allowing precise identification is presented. Moreover, the topographical distribution of myoclonus, the temporal pattern of muscle recruitment, the condition of occurrence and the rhythm of the event, may provide clinical clues relevant to the diagnosis. Myoclonus without associated epilepsy, myoclonus with epilepsy, myoclonus with encephalopathy, parkinsonism and/or dementia represent overlapping clinical categories, although they remain useful for the diagnostic approach. Using electrophysiology (including back-averaging EEG, MEG, SEP, C-reflex studies) to determine the origin of myoclonus may not allow us to focus on the underlying condition. Indeed, in many instances, the myoclonus is cortical in origin, but the pathology is found elsewhere.
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PMID:[Myoclonus in the adult: diagnostic approach]. 1128 Oct 67

Clinical features in bilateral striopallidodentate calcinosis (BSPDC), popularly referred to as Fahr's disease (five autosomal dominant families and eight sporadic cases, n = 38), recruited through a registry, are reported. Applying uniform criteria, cases reported in the literature (n = 61) were combined for detailed analysis. The mean (+/- S.D.) age of Registry patients was 43 +/- 21 and that of literature was 38 +/- 17. In combined data set (n = 99), 67 were symptomatic and 32 were asymptomatic. Of the symptomatic, the incidence among men was higher compared with women (45:22). Movement disorders accounted for 55% of the total symptomatic patients. Of the movement disorders, parkinsonism accounted for 57%, chorea 19%, tremor 8%, dystonia 8%, athetosis 5%, and orofacial dyskinesia 3%. Overlap of signs referable to different areas of central nervous system (CNS) was common. Other neurologic manifestations included: cognitive impairment, cerebellar signs, speech disorder, pyramidal signs, psychiatric features, gait disorders, sensory changes, and pain. We measured the total volume of calcification using an Electronic Planimeter and Coordinate Digitizer. Results suggest a significantly greater amount of calcification in symptomatic patients compared to asymptomatic patients. This study suggests that movement disorders are the most common manifestations of BSPDC, and among movement disorders, parkinsonism outnumber others.
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PMID:Bilateral striopallidodentate calcinosis: clinical characteristics of patients seen in a registry. 1129 78

Involuntary movements or hyperkinesias are classified into syndromes of chorea, ballism, tremor, dystonia, myoclonus and tics. The hyperkinesias are caused by disturbances in the circuitry connecting the cerebral cortex, thalamus, basal ganglia and cerebellum. Drugs are a common cause of movement disorders. The aim of management is to characterise the movement disorder, identify and treat the cause or institute symptomatic treatment. The genetic basis of many movement disorders is increasingly recognised. Where there are potential implications for family members, accurate diagnosis and counselling are particularly important.
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PMID:6: Movement disorders II: the hyperkinetic disorders. 1134 89

Abnormal involuntary movements are common symptoms in children. The neuroanatomical basis for these movement disorders is the extrapyramidal system. Although present at rest they may be more intensive during the will - depending motor activity and increased under stress. They are almost absent during sleep. The underlying causal factors of involuntary movement disorders include metabolic disorders, progressive neurodegenarative diseases, central nervous system infection. The symptomatology of chorea, athetosis, dystonia, tremor, myoclonus and tics are discussed. Special attention is paid to differential diagnosis of myoclonus, chorea and tics as well as to movement disorders and epilepsy.
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PMID:[Symptomatology of movement disorders in children]. 1167 82

Dermatitis herpetiformis and coeliac disease are gluten sensitive diseases, which have common immunopathological and genetic mechanisms. Neuropsychiatric complications have been reported in up to 26% of patients with coeliac disease. This is probably an overestimate, because of the chance associations with some common neurological conditions such as epilepsy. The pathogenesis is speculative but it has been postulated that gluten is neurotoxic possibly via immune mechanisms. The frequency of neurological dysfunction in patients with dermatitis herpetiformis has not been characterised. Patients with dermatitis herpetiformis might be expected to be particularly susceptible to neuronal damage as some continue to consume gluten when their dermatological symptoms are controlled by dapsone. Thirty five patients were recruited with dermatitis herpetiformis from dermatology clinics at St Mary's Hospital, London and Queen's Medical Centre, Nottingham and investigated for evidence of neurological abnormality. All patients underwent a full neurological examination and were asked about their neurological and general medical history by means of a structured questionnaire. Serum samples were taken and screened for the presence of anti-neuronal antibodies (anti-Hu and Yo) as well as anti-gliadin (IgA and G) anti-endomysial (IgA), and anti-tissue transglutaminase (IgA) antibodies. Neurophysiological tests were carried out where appropriate. Only two patients were identified with unexplained neurological abnormalities (one essential tremor, and one chorea). Two other patients had a history of migraine. The patient with chorea also had borderline/equivocally positive anti-Hu antibodies by immunofluorescence assay. All other samples were negative for anti-neuronal antibodies. Fifteen patients were positive for anti-gliadin antibodies (IgA and/or IgG), four for anti-endomysial antibodies (monkey oesophagus or umbilical cord), and six for anti-tissue transglutaminase antibodies. The presence of these antibodies did not correlate with the presence of neurological abnormalities. No cases of "gluten ataxia" were identified. In conclusion, there was no convincing evidence for immune mediated neurological damage in this pilot study of dermatitis herpetiformis.
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PMID:Dermatitis herpetiformis and neurological dysfunction. 1179 79

An expanded polyglutamine domain in huntingtin underlies the pathogenic events in Huntington disease (HD), characterized by chorea, dementia and severe weight loss, culminating in death. Transglutaminase (TGase) may be critical in the pathogenesis, via cross-linking huntingtin. Administration of the TGase competitive inhibitor, cystamine, to transgenic mice expressing exon 1 of huntingtin containing an expanded polyglutamine repeat, altered the course of their HD-like disease. Cystamine given intraperitoneally entered brain where it inhibited TGase activity. When treatment began after the appearance of abnormal movements, cystamine extended survival, reduced associated tremor and abnormal movements and ameliorated weight loss. Treatment did not influence the appearance or frequency of neuronal nuclear inclusions. Unexpectedly, cystamine treatment increased transcription of one of the two genes shown to be neuroprotective for polyglutamine toxicity in Drosophila, dnaj (also known as HDJ1 and Hsp40 in humans and mice, respectively). Inhibition of TGase provides a new treatment strategy for HD and other polyglutamine diseases.
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PMID:Prolonged survival and decreased abnormal movements in transgenic model of Huntington disease, with administration of the transglutaminase inhibitor cystamine. 1182 98

Hyperkinetic movement disorders such as dystonia, chorea, ballism, myoclonus, tics, and tremor may be idiopathic or symptomatic in origin. Symptomatic movement disorders need further diagnostic testing in order to identify their etiology. In addition to clinical findings, imaging techniques, and electrophysiological testing, laboratory studies are required. Here, we review the prevalence of diseases presenting with symptomatic hyperkinetic movement disorders and discuss the diagnostic relevance of laboratory studies.
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PMID:[Laboratory diagnosis of hyperkinetic movement disorders in adulthood]. 1197 89


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