(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.
Cinchona
Definition:
(n.) A genus of trees growing naturally on the Andes in Peru and adjacent countries, but now cultivated in the East Indies, producing a medicinal bark of great value.
(n.) The bark of any species of Cinchona containing three per cent. or more of bitter febrifuge alkaloids; Peruvian bark; Jesuits' bark.
Example Sentences:
(1) Comparison with two other methods showed that this procedure yields the total amount of cinchona alkaloids present in serum, which makes it extremely useful for routine clinical analysis.
(2) To buy the best species, Cinchona calisaya, one needs a perfect knowledge of these trees.
(3) Purgatives, emetics, opium, cinchona bark, camphor, potassium nitrate and mercury were among the most widely used drugs.
(4) The results suggest that cinchona alkaloids might affect myocardial contractility by their effects on Ca++ handling by SRV.
(5) Various methods and drugs were recommended and used for the therapy of depression in the 19th century, such as baths and massage, ferrous iodide, arsenic, ergot, strophantin, and cinchona.
(6) The specificity is based on quenching of the fluorescence of cinchona alkaloids by chloride ions.
(7) In vitro studies with quinine, quinidine, cinchonine, and cinchonidine showed that despite a similarity of chemical structure, the effectiveness of these cinchona bark alkaloids against several culture lines of Plasmodium falciparum varied widely.
(8) We have compared the in-vitro interactions of quinine and cinchonine, two alkaloids from cinchona bark, with human neutrophil functions.
(9) The intramolecular aliphatic N-O distance in enpiroline was 2.80 A (1 A = 0.1 nm), which is close to the N-O distance found in the antimalarial cinchona alkaloids.
(10) This component was less sensitive than the endogenous transporter to inhibition by the Cinchona bark alkaloids quinine, quinidine, cinchonine and cinchonidine, but showed a much greater sensitivity than the native system to inhibition by piperine.
(11) The assay is demonstrated using extracts of cultured Cinchona ledgeriana cells.
(12) The stem bark and stem wood of Cinchona pubescens were found to owe their weak cytotoxic activity to the presence of quinovic acid.
(13) A TLC--colorimetric method also is described for the assay of quinine and quinidine in the presence of cinchonine, cinchonidine, and other cinchona alkaloids.
(14) Using the inhibition assay for monitoring, the extracts of Hydrangea Dulcis folium, Scopoliae rhizoma, Cinchona cortex, Magnoliae cortex, Stephania tuber, and Rauwolfia radix were analysed to characterize the active constituents.
(15) This work summarises the clinical pharmacology of quinine, a cinchona alkaloid, whose use in chloroquine resistant Plasmodium falciparum malaria is of great value considering the staggering effects the infection and its morbidity have upon social and economic development of malaria endemic areas of the world.
(16) In addition, the dihydro contaminants of the cinchona alkaloids were also metabolized by aldehyde oxidase to the 2-quinolone derivatives.
(17) Charles Ledger, a British general tradesman, was able to achieve that thanks to his alert spirit of observation, his (and that of his Bolivian servant Manuel) long experience of the Andes, and the chance that brought them to fall upon a group of exceptional cinchonas which had grown on an impervious slope of the Andes.
(18) Quinine, a cinchona alkaloid, was investigated for putative anxiogenic activity in view of clinical reports suggesting that it induces anxiety and apprehension following its use in malaria.
(19) Combinations of cinchona bark alkaloids could thus be of interest in areas where P. falciparum is becoming less susceptible to quinine.
(20) The use of high-performance liquid chromatography (HPLC) interfaced with thermospray (TSP) mass spectrometry is described for the separation and identification of various alkaloids from Cinchona ledgeriana extracts.