Search results for "uci"
showing 10 items of 5317 documents
The 5-HT and alpha-adrenoceptor antagonist effect of four benzylisoquinoline alkaloids on rat aorta.
1998
Abstract The action of four benzylisoquinoline alkaloids (two aporphines—glaucine and apomorphine, a benzylisoquinoline—papaverine and a bisbenzyltetrahydroisoquinoline—antioquine) on 5-HT-induced contraction in rat thoracic aorta has been examined and compared with that of the control drugs: ketanserin, nifedipine, prazosin and phentolamine. The relaxant action on 5-HT-induced contraction was contrasted with that on the contraction induced by noradrenaline and KCl. The results obtained with control drugs show that ketanserin has clear selectivity for 5-HT receptors, whereas prazosin and phentolamine have high selectivity for the α1-adrenoceptor and nifedipine seems to have a more potent ef…
Research on Acute Toxicity and the Behavioral Effects of Methanolic Extract from Psilocybin Mushrooms and Psilocin in Mice
2015
The pharmacological activities and acute toxicity of the psilocin (PC) and dried residues of the crude extracts of psychotropic mushrooms were investigated in mice. The hallucinogenic substances were effectively isolated, by using methanol, from the species of Psilocybe semilanceata and Pholiotina cyanopus, that were collected in the north-east region of Poland. The chemical analysis of these extracts, which was performed by liquid chromatography with mass spectrometry detection (LC-MS), indicated the presence of psilocin and other hallucinogenic substances, including indolealkylamines and their phosphorylated analogues. When the pure psilocin or fungal extracts were used, slight difference…
Selection and characterization of a novel agonistic human recombinant anti-Trail-R2 minibody with anti-leukemic activity
2009
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising natural anticancer therapeutic agent because through its “death receptors”, TRAIL-R1 and TRAIL-R2, it induces apoptosis in many transformed tumor cells, but not in the majority of normal cells. Hence, agonistic compounds directed against TRAIL death receptors have the potential of being excellent cancer therapeutic agents, with minimal cytotoxicity in normal tissues. Here, we report the selection and characterization of a new single-chain fragment variable (scFv) to TRAIL-R2 receptor isolated from a human phage-display library, produced as minibody (MB), and characterized for the in vitro anti-leukemic tumoricid…
La agricultura a tiempo parcial y la externalización de servicios agrarios como vehículo del cambio estructural
2010
El «ajuste clásico» ha sido interpretado frecuentemente como la senda racional y óptima de modernización del sector agrario. Esto ha llevado a considerar a la agricultura a tiempo parcial como un subproducto (ineficiente) del modelo clásico. Frente a este planteamiento, el artículo defiende la potencial contribución de la agricultura a tiempo parcial (y la externalización de servicios asociada a la misma) al proceso de innovación y de modernización de las estructuras agrarias. Se revisa críticamente la literatura adoptando una perspectiva microeconómica y territorial y esbozando un marco analítico que combina los enfoques de los costes de transacción y evolucionista. Utilizando información …
Pitfalls to be considered on the metabolomic analysis of biological samples by HR-MAS
2014
HR-MAS (High-Resolution Magic AngleSpinning) is considered a powerfultechnique for metabolomic studies ofbiological samples that provides “intact”tissue spectra (Cheng et al., 1998; Waterset al., 2000; Sitter et al., 2002; Martinez-Bisbal et al., 2004; Payne et al., 2006;Coen et al., 2007; Bathen et al., 2010).The performance of HR-MAS, fol-lowed by quantitative histopathology hasdemonstrated that, despite some changes,HR-MAS can preserve approximately thetissue histopathologic features producingwell-resolved spectra of cellular metabo-lites (Cheng et al., 2000). Nevertheless,therearesomeaspectsarousedintheliter-ature about the possible biochemical andstructural changes that can occur durin…
Stereocontrolled synthesis of D-α-hydroxy carboxylic acid from L-amino acids
1987
Abstract Optically active D-α-hydroxy carboxylic acids are obtained from L-amino acids via L-α-halocarboxylic acids and their stereoselective reaction with cesium p-nitrobenzoate.
Determinants of Substrate Specificity in the NS3 Serine Proteinase of the Hepatitis C Virus
1997
AbstractProcessing of the nonstructural polyprotein of the hepatitis C virus (HCV) requires the serine-type proteinase located in the amino-terminal domain of NS3. To identify residues within NS3 determining substrate specificity, a mutation analysis was performed. Using sequence alignments and three-dimensional structure predictions, amino acids assumed to be important for specificity were replaced and the enzymes were tested in an intracellulartrans-processing assay for their effects on cleavage of an NS4B-5B substrate. For some of the substitutions at positions 133, 134, 135, 136, 138, 152, 155, 157, and 169, slightly reduced processing efficiencies were observed but in no case was the s…
Classification of vegetable oils according to their botanical origin using amino acid profiles established by direct infusion mass spectrometry.
2007
Amino acid profiles, established by direct infusion mass spectrometry, have been used to classify vegetable oils according to their botanical origin. The proteins present in hazelnut, sunflower, corn, soybean, olive, avocado, peanut and grapeseed oils were precipitated with acetone, and the residue was hydrolyzed in acid medium, diluted in a hydrochloric acid/ethanol mixture, and infused into the mass spectrometer. The spectra of the hydrolyzed protein extracts showed [M+H]+ ions of the following amino acids: glycine, alanine, serine, proline, valine, threonine, cysteine, isoleucine + leucine, aspartic acid, lysine, glutamic acid, methionine, histidine, phenylalanine, arginine and tyrosine.…
Determination of alcohols in essential oils by liquid chromatography with ultraviolet detection after chromogenic derivatization
2013
Abstract An HPLC-UV method to determine compounds having a hydroxyl functional group in plant essential oils is developed. The sample is diluted with 1,4-dioxane and the analytes are derivatized with phthalic anhydride. The derivatives (phthalates hemiesters) are separated on a C8 column using an acetonitrile (ACN)/water gradient. Separation conditions were optimized using the DryLab® method development software. For the alcohols and phenols present in mint and rose essential oils, optimization led to a ca. 40 min gradient time and a column temperature of 8 °C. The alcohol and its derivatives were identified using HPLC with mass spectrometry (MS) detection. A large sensitivity enhancement w…
La partícula modal doch entre el modo oracional declarativo e interrogativo y sus equivalentes en español
1997
En este artículo se lleva a cabo un estudio lingüístico-contrastivo de la partícula modal (en adelante: PM) alemana doch en oraciones declarativas e interrogativas y sus equivalentes en español, cuyo sistema carece de una clase lexemática de PMs (Modalpartikeln) bien determinada como en alemán. Las lenguas románicas, como el francés (Weydt, 1969), el españ,ol (Zierer, 1978) o el catalán, carecen en general de PMs como grupo lexemático con una función común. Pero en las lenguas en las que no se puede establecer una clase lexemática equivalente a las PMs alemanas también podemos hallar recursos suficientes para expresar los significados aportados por ellas.