Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027497 (nausea)
 23,468 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nausea and emesis are significant side effects in patients undergoing stereotactic radiosurgery for brain lesions in the region of the chemoreceptor trigger zone (area postrema of the brain). Even with the current antiemetic treatment (prochlorperazine +/- corticosteroids), those side effects remain significant. The purpose of this study is twofold: [1] to evaluate the efficacy of ondansetron in inhibiting nausea and emesis in stereotactic radiosurgery patients and [2] to demonstrate that ondansetron's locus of action is the central nervous system (CNS) chemoreceptor trigger zone in the area postrema. In a pilot study, 10 patients receiving > or = 350 cGy in a single fraction of radiosurgery to the region of the area postrema received 32 mg ondansetron iv 1 hour prior to treatment +/- corticosteroids. In a retrospective analysis these results were compared to those of patients with similar features (and matched for radiation dose to the area postrema and the dose of corticosteroids) who received prochlorperazine +/- corticosteroids. Nine of 10 patients in the ondansetron group had no nausea or emesis within 48 hours after treatment; one patient experienced one episode of emesis. In the prochloreperazine group, eight patients had symptoms, three patients needed hospitalization or a physician's care for emesis within 24 hours, and five had nausea with no specific treatment. These preliminary results suggest that ondansetron is a safe and efficient drug to prevent nausea and emesis in this patient group. The precise mechanism of action of ondansetron in these patients is unknown, but is likely due to the drug's serotonin-blocking effect within the CNS. A randomized, prospective study has been started at our institution to confirm these preliminary results.
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PMID:The prevention of radiosurgery-induced nausea and vomiting by ondansetron: evidence of a direct effect on the central nervous system chemoreceptor trigger zone. 794 Jan 14

A substantial body of evidence indicates that aged-related changes in the fluidity and lipid composition of the plasma membrane contribute to cellular dysfunction in humans and other mammalian species. In the CNS, reductions in neuronal plasma membrane order (PMO) (i.e., increased plasma membrane fluidity) have been attributed to age as well as the presence of the beta-amyloid peptide-25-35, known to play an important role in the neuropathology of Alzheimer's disease (AD). These PMO increases may influence neurotransmitter synthesis, receptor binding, and second messenger systems as well as signal transduction pathways. The effects of neuronal PMO on learning and memory processes have not been adequately investigated, however. Based on the hypothesis that an increase in PMO may alter a number of aspects of synaptic transmission, we investigated several neurochemical and behavioral effects of the membrane ordering agent, PF-68. In cell culture, PF-68 (nmoles/mg SDS extractable protein) reduced [3H]norepinephrine (NE) uptake into differentiated PC-12 cells as well as reduced nicotine stimulated [3H]NE release. The compound (800-2400 microg/kg, i.p., resulting in nmoles/mg SDS extractable protein in the brain) decreased step-through latencies and increased the frequencies of crossing into the unsafe side of the chamber in inhibitory avoidance training. In the Morris water maze, PF-68 increased the latencies and swim distances required to locate a hidden platform and reduced the time spent and distance swam in the previous target quadrant during transfer (probe) trials. PF-68 did not impair performance of a well-learned working memory task, the rat delayed stimulus discrimination task (DSDT), however. Studies with 14C-labeled PF-68 indicated that significant (pmoles/mg wet tissue) levels of the compound entered the brain from peripheral (i.p.) injection. No PF-68 related changes were observed in swim speeds or in visual acuity tests in water maze experiments, rotorod performance, or in tests of general locomotor activity. Furthermore, latencies to select a lever in the DSDT were not affected. These results suggest that PF-68 induced deficits in learning and memory without confounding peripheral motor, sensory, or motivational effects at the tested doses. Furthermore, none of the doses induced a conditioned taste aversion to a novel 0.1% saccharin solution indicating a lack of nausea or gastrointestinal malaise induced by the compound. The data indicate that increases in neuronal plasma membrane order may have significant effects on neurotransmitter function as well as learning and memory processes. Furthermore, compounds such as PF-68 may also offer novel tools for studying the role of neuronal PMO in mnemonic processes and changes in PMO resulting from age-related disorders such as AD.
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PMID:Plasma membrane ordering agent pluronic F-68 (PF-68) reduces neurotransmitter uptake and release and produces learning and memory deficits in rats. 1064 67

Exposure of rats to high-energy iron particles (600 MeV/amu) has been found to alter behavior after doses as low as 10 rads. The performance of a task that measures upper body strength was significantly degraded after irradiation. In addition, an impairment in the regulation of dopamine release in the caudate nucleus (a motor center in the brain), lasting at least 6 months, was also found and correlated with the performance deficits. A general indication of behavioral toxicity and an index of nausea and emesis, the conditioned taste aversion, was also evident. The sensitivity to iron particles was 10-600 times greater than to gamma photons. These results suggest that behavioral and neurobiological damage may be a consequence of exposure to low doses of heavy particles and that this possibility should be extensively studied.
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PMID:Behavioral and neurochemical abnormalities after exposure to low doses of high-energy iron particles. 1153 13

Neuromyelitis optica (NMO) is an inflammatory demyelinating disorder that predominantly affects the optic nerve and spinal cord; however, symptomatic brain involvement is not rare and is sometimes an initial manifestation in NMO. In this study, we investigated the characteristic features of patients with NMO with symptomatic brain involvement as the initial manifestation of disease (NMO(brain)) compared with patients with NMO who presented initially with optic neuritis or myelitis (NMO(ON/myelitis)). We retrospectively reviewed 27 consecutive Korean patients with NMO with aquaporin-4 antibodies. Patients with NMO(brain) (n=9) initially presented with intractable hiccup/nausea/vomiting and/or encephalopathy at a younger age than the patients with NMO(ON/myelitis) (n=18) (p<0.01). During the disease course, the patients with NMO(brain) continued to show more frequent symptomatic involvement of the brain than the 18 patients with NMO(ON/myelitis) (p<0.05). At the final visit, the mean age was also significantly lower in patients with NMO(brain) than in patients with NMO(ON/myelitis) (p<0.01); however, the Expanded Disability Status Scale scores, used to evaluate disease progression, were not different between the two groups. Our study suggests that patients with NMO who present initially with symptomatic brain involvement may have earlier disease onset and become disabled at a younger age compared to patients with typical NMO. Additional large scale prospective studies are warranted.
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PMID:Symptomatic brain involvement as the initial manifestation of neuromyelitis optica. 2367 42