(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.
Brucine
Definition:
(n.) A powerful vegetable alkaloid, found, associated with strychnine, in the seeds of different species of Strychnos, especially in the Nux vomica. It is less powerful than strychnine. Called also brucia and brucina.
Example Sentences:
(1) The strychnine-like effect was common to other glycine-antagonist tested, such as brucine, morphine and laudanosine.
(2) The hyper-irritability elicited by picrotoxin or penicillin G-K was associated with a relatively localized trigger zone in the face, while that elicited by strychnine or brucine spread beyond the trigeminal region to the first cervical dermatome.
(3) In the presence of large amounts of strychnine, brucine is isolated prior to colorimetric analysis by a quantitative thin layer chromatographic technique.
(4) This paper reports the determination of strychnine and brucine in different parts of Semen Strychni (the seeds of Strychnos nux-vomica and S. pierriana), and makes a comparison of the contents between the crude forms and processed products of the two seeds.
(5) Bisnor-dihydrotoxiferine seems to give dichlorometho compounds and N-oxides easily, analogous with strychnine and brucine.
(6) When the effects of quinine, brucine and caffeine on electrical responses in taste cells were examined, they all produced a depolarization associated with an increased input resistance.
(7) Sodium chloride (1,000 mM) enhanced the affinity of strychnine, brucine, isostrychnine, and the nonselective GABA antagonist pitrazepin for [3H]strychnine binding sites, whereas the affinities of glycine, beta-alanine, and taurine were reduced.
(8) The second was developed for the determination of brucine and is based on measuring the intensity of the violet color produced by treating brucine with nitric acid and methanolic stannous chloride.
(9) In contrast, brucine, the 2,3-dimethoxy derivative of strychnine, caused no increase in duplication frequencies under the identical conditions.
(10) The TMA curves of brucine, griseofulvin and phenobarbital were similar to that of indomethacin.
(11) We found that inferior olive lesioned rats had lower threshold to seizures induced by strychnine and brucine, both glycine antagonists.
(12) The natural abundance 13C-NMR spectra of brucine and strychnine were obtained using the pulse Fourier transform technique.
(13) The paper reports the experimental result of the simultaneous quantitative determination of strychnine (ST) and brucine(BR) in Semen Strychni by dual wavelength spectrophotometry.
(14) Nitrate were determined by the brucine method, while nitrates by the Griess colorimetric method.
(15) The CMA was thought to be of L(+)-form based on the results of optical resolution with brucine and also its susceptibility to L(+)-citramalate lyase of Clostridium tetanomorphum.
(16) In vitro, amoxapine and brucine most effectively reversed the inhibitory action of GABA on 35S-TBPS binding.
(17) Binding was completely inhibited by glycine, alanine, alpha-aminobutyric acid, beta-aminoisobutyric acid, hypotaurine and strychnine, and to a lesser extent by 2,2-dimethyl-beta-alanine, brucine and gelsemine.
(18) On heat treatment, the contents of the major alkaloids such as strychnine and brucine declined significantly with increases in the amounts of isostrychnine, isobrucine, strychnine N-oxide and brucine N-oxide.
(19) 5-(3-Hydroxyphenyl)-5-phenylhydantoin (m-HPPH) has been resolved by crystallization of the brucine salts.
(20) Contents of strychnine and brucine in dry seeds of Strychnos nux-vomica and its preparations were determined by gas chromatography.