What's the difference between alkaloid and physostigmine?
Alkaloid
Definition:
(a.) Alt. of Alkaloidal
(n.) An organic base, especially one of a class of substances occurring ready formed in the tissues of plants and the bodies of animals.
Example Sentences:
(1) Thus, alkaloid and insecticide modifications share many features but differ in how much the conducting properties of the pore are changed and whether the channel can close reversibly while the toxin remains bound.
(2) A clear structure-mutagenicity relationship was observed in a series of aporphine alkaloids (aporphine, dehydroaporphine, 7-oxoaporphine and 4,5-dioxoaporphine), and 10,11-non-substituted aporphines were suggested to exert their mutagenicity through metabolic activation of the 10,11 positions, possibly as the 10,11-epoxides.
(3) A radioactive, photoactive Vinca alkaloid, N-(p-azido-[3,5-3H]-benzoyl)-N'-beta-aminoethylvindesine [( 3H]NABV) with pharmacological and biological activities similar to vinblastine was synthesized and used to identify specific Vinca alkaloid macromolecular interactions in calf brain homogenate by photoaffinity labeling.
(4) The comparative metabolism of the pyrrolizidine alkaloid (PA) senecionine was studied in vitro in incubations of rat, guinea pig, cow, horse, and sheep hepatic microsomes.
(5) They also displayed negative correlation between activities of protein-inhibitors and the total content of protein and alkaloids.
(6) Methods have been reviewed for alkylating agents, platinum compounds, antitumour antibiotics, antimetabolites, alkaloids, suramin, 1-hydroxy-3-amino-propylidene-1,1-bisphosphonate and tamoxifen.
(7) The resistant strains exhibited cross resistance to anthracycline antibiotics, vinca alkaloids, actinomycin D, colchicine.
(8) In mice treated with cepharanthine (Cepha), a biscoclaurine alkaloid, the number of T cells was increased in the parathymic lymph nodes (PtLNs) which are considered to be the specialized lymph nodes in local differentiation of T cells.
(9) The alkaloid tubulosine inhibits the process of peptide chain elongation by eukaryotic polysomes by specifically preventing the elongation-factor-2-dependent step of translocation.
(10) Cultured roots of Stephania cepharantha, which are rich sources of bisbenzylisoquinoline alkaloids, were fed 14C-labelled tyrosine, tyramine or dopamine.
(11) As a possible mechanism underlying the alterations of DRP, the functional consequences of atrophic changes of primary central afferent terminals are being discussed in terms of the close correlation between structure and function and the possible inferences of the electrophysiological reaction to the therapeutic application of Vinca alkaloids in the iontophoretic treatment of chronic intractable pain.
(12) The poisonous principles in tansy ragwort are pyrrolizidine alkaloids, which cause gradual alteration and necrosis of liver cells with replacement by fibrous tissue.
(13) In this study, the roots of Tabernaemontana heyneana Wall were examined and the isolation and identification of additional indole alkaloids and some pharmacological properties of coronaridine are described.
(14) The area ratios of four alkaloids (tropacocaine, norcocaine, cis-cinnamoylcocaine, and trans-cinnamoylcocaine) to cocaine are calculated for each sample.
(15) The main drugs with specific action on migraine include ergot alkaloids (ergotamine, dihydroergotamine), agonists (sumatriptan) or partial agonists (methysergide) at a specific subtype of 5-HT1-like receptors, beta-adrenoceptor antagonists (propranolol, metoprolol), calcium antagonists (flunarizine) and anti-inflammatory agents (indomethacin).
(16) Effects of solution variables on the binding and self-association explain the wide variation of reported apparent binding constants for Vinca alkaloids to tubulin.
(17) The concomitance of five previously reported trans-2,5-dialkyl-pyrrolidines along with small amounts of the cis isomers and N-methyl analogues makes the venom of M. indicum the most qualitatively diverse blend of alkaloids reported from an ant to date.
(18) Strong enhancement of delayed-type hypersensitivity (DTH) was observed after treatment with the active cyclophosphamide (CY) derivative Z 7557 or the plant alkaloid VP-16 at the site of sensitization.
(19) A total alkaloid and two purified alkaloid extracts of Alangium Vitiense were revealed by our experimental screening to be oncostatic on L1210 leukemia and two other lymphoid neoplasias in Mice.
(20) Possible mechanisms underlying these effects of insecticides on alkaloid-dependent uptake are discussed in light of a qualitative model formulated from these results and previous biochemical and electrophysiological studies.
Physostigmine
Definition:
(n.) An alkaloid found in the Calabar bean (the seed of Physostigma venenosum), and extracted as a white, tasteless, substance, amorphous or crystalline; -- formerly called eserine, with which it was regarded as identical.
Example Sentences:
(1) injection of the tertiary amine cholinesterase inhibitor physostigmine (17-70 micrograms kg-1) induced a prompt, sustained and dose-dependent improvement of cardiovascular and respiratory function, with marked increase in the volume of circulating blood and survival of all treated animals, at least for the 2 h of observation.
(2) Drugs known to improve memory, including physostigmine, pramiracetam and the muscarinic agonists, oxotremorine and RS 86, selectively induced analgesia in rats subjected to test before the shock plus the shock, thereby supporting a hypothesis of avoidance learning.
(3) Plasma and brain containing physostigmine were first precipitated with TCA, and then carbaryl was added.
(4) In the presence of physostigmine the two sources of stimuli were equally effective.
(5) The study of the drugs effective in the treatment of cognitive deficits and memory loss associated with senile dementia of the Alzheimer's type--tacrine and amiridin, acetylcholinesterase inhibitor physostigmine and nootrop piracetam on uptake of 3H-serotonin (3H-5-HT), 3H-adrenaline (3H-AD), 3H-noradrenaline (3H-HA), 2H-dopamine (3H-DA), 3H-gamma-aminobutyric acid (3H-GABA), 3H-glutamic acid (3H-GLU), 3H-aspartic acid (3H-ASP) and 3H-glycine (3H-GLI) showed that tacrine and amiridin (5 x 10(-5) M) statistically significantly (P less than 0.05) inhibited the uptake of 3H-DA and 3H-5-HT.
(6) The present results demonstrate that either the presurgical drug treatment (desmethylimipramine and pentobarbital) or 7 days isolation was alone sufficient to reduce the yawning response to physostigmine and abolish its potentiation by nifedipine.
(7) Predicted concentrations of physostigmine in different tissue compartments were consistent with the experimental observations in the rat following an iv dose.
(8) Acute exercise modifies the effect of physostigmine significantly (p less than 0.01) by increasing the cholinesterase inhibition in red blood cells and brain without affecting other tissues.
(9) The time of survival of DFP exposed animals increased after pretreatment with carbamates, more after physostigmine (81 min) than after pyridostigmine (59 min).
(10) To examine the efficacy of cholinergic enhancement in senile dementia of the Alzheimer type (SDAT), oral physostigmine was given to eight patients in a cross-over trial of three dose levels and a matching placebo.
(11) In a group of the MS-DB units with stable background theta bursts the typical response consisting of entrainment of the phase-locked theta cycles was changed neither by physostigmine, nor by cholinergic-blocking drugs (scopolamine and atropine).
(12) Aimed at the centralized manufacture of physostigmin salicylate injection solutions, the efficacy of different stabilizators has been studied under conditions of the thermic load.
(13) The kinetics of the nicotine effects on uptake were different from those of physostigmine.
(14) For example, scopolamine elicits increased locomotor activity, an action which is attenuated by glucose and by combined treatment with glucose and physostigmine at doses which are individually without effect.
(15) The effect of physostigmine on recent memory was evaluated in young and aged rhesus monkeys.
(16) After oral physostigmine administration the following morning, the majority of patients experienced side effects such as nausea and abdominal pain.
(17) To assess the efficacy of oral physostigmine for the treatment of Alzheimer's disease, 20 patients were entered into a clinical trial.
(18) These retention deficits could be reversed by the postacquisition administration of the acetylcholinesterase inhibitor, physostigmine.
(19) Atropine reduced the dopamine-induced secretion significantly, and physostigmine enhanced the secretion.
(20) Serum butyrylcholinesterase (EC 3.1.1.8) appears to be responsible for this hydrolysis, as evidenced by its inhibition by physostigmine and catalysis by commercially available pseudocholinesterase from horse and human blood.