Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0028738 (nystagmus)
 7,431 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Actions and interactions of buprenorphine (BUP) and amitriptyline (AMI) on performance and respiration were studied double-blind and cross-over in 12 healthy volunteers. After one-week pretreatments with AMI or placebo, the subjects received on Day 8 placebo, BUP or AMI so that the final treatments were 1) placebo, 2) acute AMI 50 mg, 3) acute BUP, 4) subchronic AMI + acute BUP and 5) subchronic AMI. The subacute treatments were started at two-week intervals. A Mapleson D rebreathing circuit including a pneumotachograph and an infrared capnograph was employed to study drug effects on respiration. Minute volume and end-tidal carbon dioxide as well as psychomotor performance were measured and the blood samples taken on Day 8 before the drug intake and 2 and 4 h thereafter. The performance tests included tracking, choice reaction, flicker fusion, exophoria, nystagmus, digit symbol substitution and the subjective assessment of mood. BUP depressed respiration, and subchronic AMI increased this depression. Both BUP and acute AMI 50 mg each alone impaired various measures of performance and rendered the subjects drowsy, feeble, mentally slow and muzzy but subchronic AMI did not enhance BUP effects. BUP increased plasma prolactin levels similarly after both pretreatments. The results suggest that both BUP and AMI moderately affect psychomotor performance but the interaction between these agents is mild and restricted mainly to respiration.
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PMID:Psychomotor, respiratory and neuroendocrinological effects of buprenorphine and amitriptyline in healthy volunteers. 369 7

Provocation tests such as head shaking and positional tests, as well as hyperventilation, have been used routinely by many laboratories to elicit nystagmus during an electronystagmogram. We added oxygen testing to this routine battery and compared the results with hyperventilation and other forms of provocative testing. Hyperventilation and oxygen testing are unique in that they probably affect the vestibular system by changing the levels of oxygen and carbon dioxide supplied. Hyperventilation in theory would decrease available oxygen, while oxygen testing would cause an increase. In a study of two groups totaling over 700 patients, we found that oxygen testing is only occasionally positive (2.5%) and is of little practical value. Hyperventilation testing is positive 8% of the time but rarely alone, and has no localizing value. When hyperventilation and oxygen tests are both positive, the nystagmus may be in opposite directions. In 6 of 18 patients with acoustic neurinomas, hyperventilation produced transitory direction-changing nystagmus.
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PMID:Study of ventilation testing with electronystagmography. 678 96

Subacute necrotizing encephalomyelopathy (Leigh's syndrome) is a rare neurodegenerative disease in the adult. The precise metabolic defect is unknown, but abnormalities of a mitochondrial enzyme system related to cytochrome-c oxidase or pyruvate dehydrogenase are described. The clinical picture usually consists of an altered breathing pattern, oculomotor paralysis, other signs of cranial nerve dysfunction, ataxia, myoclonic jerks, nystagmus, generalized seizures, optic atrophy and demyelinating peripheral neuropathy. Hypopnea leads to CO2-retention with consecutive loss of consciousness demanding mechanical ventilation. Respiratory failure is the most frequent cause of death. Here we describe two patients with adult onset Leigh's syndrome and we discuss the longterm treatment strategies including vitamin B1 and CPAP mask.
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PMID:[Adult Leigh syndrome. A rare differential diagnosis of central respiratory insufficiency]. 771 56

Vertigo related to acidosis in Meniere's disease has been reported. This study was undertaken to ascertain whether acidosis has any effect on vertigo. Since patients with Meniere's disease usually show unilateral vestibular dysfunction, unilateral intratympanic injection of streptomycin sulfate (SM) was used to induce unilateral vestibular dysfunction in rabbits. Intratympanic SM injections induced vestibular destruction and elicited severe spontaneous nystagmus and ataxia. Then symptoms of acute vestibular upset gradually subsided and eventually disappeared completely. Three weeks after SM injections, in compensated rabbits, NH4Cl injection or CO2 inhalation was used to induce acidosis. Intravenous NH4Cl injection or CO2 inhalation induced nystagmus and ataxia again. In normal rabbits, no nystagmus was induced by NH4Cl injection or by CO2 inhalation. These results suggest that acidosis might be a cause of recurrence of vertigo in patients with unilateral vestibular dysfunction.
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PMID:Effect of experimental acidosis on nystagmus in rabbits. 820 92

A 32-year-old male commercial diver was working at 7,000 feet of altitude in a municipal water tank, at a depth of 27 feet for two hours. While surfacing from a compressed-air surface-supplied dive, he exhibited loss of consciousness and neurological symptoms. He was presumptively diagnosed with arterial gas embolism, flown by pressurized aircraft to a regional medical center and treated with hyperbaric oxygen. During the U.S. Navy Treatment Table 6, new information suggested the patient's air supply had been contaminated by a continuously running engine and compressor. His admission blood was then assayed for carboxyhemoglobin (COHb), which measured 8.8% six hours after surfacing, including four hours of normobaric oxygen inhalation. His estimated COHb based on rough reported half-life calculations at the conclusion of the dive was approximately 45%. The patient's diagnosis was changed to carbon monoxide poisoning from contaminated breathing gas. Upon hospital discharge, he exhibited problems with balance and gait, nystagmus, word-finding limitations and slurred speech. Also, he had cardiac injury treated with carvedilol. When evaluating diving-related casualties, including in commercial divers, clinicians should consider carbon monoxide poisoning as a differential diagnosis.
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PMID:Carbon monoxide poisoning mimicking arterial gas embolism in a commercial diver. 2253 Apr 51