Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0917801 (insomnia)
 10,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Raynaud's phenomenon has been considered to be due to activation of the central sympathetic vasoconstrictor reflex, and may represent part of a larger dysfunction of higher autonomic centers. Symptoms, such as sweating disturbances, orthostatic hypotension, insomnia and impotence have been reported to be more common among vibration exposed workers. We studied 217 male forest workers and selected samples of this population for electromyographic (N = 80), autonomic nervous system function, controlled breathing, tilting bed and valsalva manoeuvre (N = 88) tests, and a full clinical neurological examination. Mean alcohol consumption was estimated to be 3.0 kg absolute alcohol/year. The total mean vibration exposure time was 14,100 hours. The prevalence of Raynaud's phenomenon was 5%. The variations in heart rate (HRV) at rest and during deep breathing were observed. The traditional indexes of HRV (CV, CVS, MEAN) were computerized and calculated. There was a significant difference (p less than 0.001) between the HRV indexes during the deep breathing test in those with the shortest and the longest exposure to vibration. The values of HRV indexes were age dependent; and in multiple regression analysis, the total exposure time to vibration had an independent negative association to HRV. Also association of sensory neural hearing loss to Raynaud's phenomenon among vibration exposed workers indicates that there is an involvement of the central nervous system in the pathogenesis of vibration syndrome. The question, does vibration cause permanent changes in autonomic centers of the brain or do these centers only mediate vibration stress to end organs, remains unsettled.
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PMID:Vibration stress and the autonomic nervous system. 238 Nov 49

Alpha methyltyrosine (alpha-MPT) was administered to 52 patients from 4 days to 10 months; 22 patients were cases of pheochromocytoma and 20 had essential hypertension. Inhibition of catecholamine synthesis in the range of 50-80% was achieved with divided daily drug dosage of from 1.0 to 4.0 g. Striking clinical benefit was noted in patients with pheochromocytoma in whom the drug was used in preparation for surgery and during chronic medical management. The drug appeared to have limited usefulness when used in essential hypertension, unless added to existing therapy with conventional agents. No beneficial effects were noted in thyrotoxicosis, glaucoma, and Raynaud's phenomenon. Untoward effects in order of decreasing incidence were: sedation (with insomnia on withdrawal), anxiety, tremor, diarrhea, and galactorrhea. Drug crystalluria, which has been observed in animals and is currently restrictive of clinical trials, was not observed in these studies. Evidence is presented that the minor conversion of alpha-MPT to methyldopa probably does not contribute significantly to the central and peripheral effects of the drug.
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PMID:Biochemical and pharmacologic effects of alpha-methyltyrosine in man. 563 45