Search results for "Reno"
showing 10 items of 1031 documents
Development of a new multi-analyte assay for the simultaneous detection of opioids in serum and other body fluids using liquid chromatography-tandem …
2015
Abstract A liquid chromatography–tandem mass spectrometry method using electrospray ionization in positive ionization mode was developed for the simultaneous detection of multiple opioid-type drugs in plasma. The presented assay allows the quantitative determination of alfentanil, buprenorphine, codeine, desomorphine, dextromethorphan, dextrorphan, dihydrocodeine, dihydromorphine, ethylmorphine, fentanyl, hydrocodone, hydromorphone, methadone, morphine, naloxone, naltrexone, oxycodone, oxymorphone, pentazocine, pethidine, pholcodine, piritramide, remifentanil, sufentanil, and tramadol as well as the metabolites 6-monoacetylmorphine, bisnortilidine, morphine-3-glucuronide, morphine-6-glucuro…
Liquid chromatographic procedure for the evaluation of β-blockers in pharmaceuticals using hybrid micellar mobile phases
1997
Abstract A reversed-phase chromatographic procedure with a micellar eluent is proposed for the determination of several β-blockers (acebutolol, atenolol, carteolol, celiprolol, labetalol, metoprolol, nadolol, oxprenolol, propranolol, and timolol) in pharmaceutical formulations (tablets, capsules, and ophthalamic solutions). A study is shown on the chromatographic behaviour of these drugs with mobile phases containing sodium dodecyl sulphate (0.075–0.15 M ) and propanol (0–15%, v/v), at different pH values (3–7). The excellent correlation between log of the octanol-water partition coefficient and log of capacity factor, for the ten drugs in mobile phases of SDS and propanol, suggested that t…
Quantitative structure-retention and retention-activity relationships of beta-blocking agents by micellar liquid chromatography.
2001
Abstract Sixteen β-blocking agents (acebutolol, alprenolol, atenolol, bisoprolol, carteolol, celiprolol, esmolol, labetalol, metoprolol, nadolol, oxprenolol, pindolol, practolol, propranolol, sotalol and timolol) showing a large range of hydrophobicity (octanol–water partition coefficients, log P between −0.026 and 2.81) were subjected to micellar liquid chromatography with sodium dodecyl sulfate as micelle forming agent, and n-propanol as organic modifier. The correlation between log P and the retention factor extrapolated to a mobile phase free of micelles and organic modifier was investigated. The use of an interpolated retention factor or the retention factor for specific individual exp…
Improvement of peak shape and separation performance of beta-blockers in conventional reversed-phase columns using solvent modifiers.
2003
A comparative study of peak shape, elution behavior, and resolution of 16 beta-blockers (acebutolol, alprenolol, atenolol, bisoprolol, carteolol, celiprolol, esmolol, labetalol, metoprolol, nadolol, oxprenolol, pindolol, practolol, propranolol, sotalol, and timolol) chromatographed with hybrid mobile phases of triethylamine (TEA)-acetonitrile and sodium dodecyl sulfate (SDS)-propanol is performed using conventional reversed-phase columns and isocratic elution. Both solvent modifiers (TEA and SDS) prevent the interaction of the basic drugs with the alkyl-bonded phase. However, the protection mechanisms of silanols on the packing are different. Whereas TEA associates with the silanol sites (b…
Micellar-organic versus aqueous-organic mobile phases for the screening of β-blockers
2002
A comparative study of the performance of reversed-phase liquid chromatography with micellar-organic (MLC) and aqueous-organic (RPLC) mobile phases is reported for the separation of 16 -blockers (acebutolol, alprenolol, atenolol, bisoprolol, carteolol, celiprolol, esmolol, labetalol, metoprolol, nadolol, oxprenolol, pindolol, practolol, propranolol, sotalol, and timolol). MLC with hybrid mobile phases of sodium dodecyl sulfate (SDS) and propanol is revealed as a very competitive technique for the screening of these drugs. Using a conventional Spherisorb C18 column, the theoretical plates ( N) and asymmetry factors (B/A) for the optimal mobile phase compositions were in the ranges N = 2200–4…
Paradoxical effect of increased diastolic Ca(2+) release and decreased sinoatrial node activity in a mouse model of catecholaminergic polymorphic ven…
2012
Background— Catecholaminergic polymorphic ventricular tachycardia is characterized by stress-triggered syncope and sudden death. Patients with catecholaminergic polymorphic ventricular tachycardia manifest sinoatrial node (SAN) dysfunction, the mechanisms of which remain unexplored. Methods and Results— We investigated SAN [Ca 2+ ] i handling in mice carrying the catecholaminergic polymorphic ventricular tachycardia–linked mutation of ryanodine receptor (RyR2 R4496C ) and their wild-type (WT) littermates. In vivo telemetric recordings showed impaired SAN automaticity in RyR2 R4496C mice after isoproterenol injection, analogous to what was observed in catecholaminergic polymorphic ventricul…
Polyunsaturated fatty acids in cultured cardiomyocytes : effect on physiology and beta-adrenoceptor function
1992
This study was carried out to investigate the influence of the membrane fatty acid composition on the basal electrical and contractile activities and the response to beta-adrenergic stimulation of rat cardiac muscle cells in culture. Cells were grown for 3 days in a conventional serum culture medium and then incubated for 24 h in synthetic media containing either n-6 or n-3 as the sole source of polyunsaturated fatty acids (PUFA). The n-6/n-3 ratio in the phospholipids was 0.9 in the n-3 cells and 13.1 in the n-6 cells compared with 6.3 in controls cells. Such modifications did not alter action potentials and the main parameters related to contraction, although shortening was slightly acce…
Fractionation of glycoside aroma precursors in neutral grapes. Hydrolysis and conversion by Saccharomyces cerevisiae
2004
Abstract Glycoconjugated aroma precursors from neutral grape varieties were fractionated on 5 g C18 RP cartridge. Each of the seven fractions collected was divided in three parts: first part was hydrolysed with Pectinol in order to determine total aromatic heterosides, while the second part was treated with an active strain of the yeast Saccharomyces cerevisiae UCLM 325 and the third part with acetonic powder of the same yeast strain. The studied strain proved effective in the hydrolysis of the heterosides of nerol and geraniol, cis-8-hydroxy-linalool, 8-hydroxy-dihydro-linalool, some benzenoids and some norisoprenoids derivatives such as vomifoliol and 3-oxo-α-ionol. Only whole cells are a…
The urban revitalization of the coastal tourist destinations: An alternative for the Valencian Mediterranean tourist municipalities
2021
espanolLos municipios del litoral mediterraneo valenciano aumentaron sensiblemente su superficie construida por la irrupcion de la actividad turistica a mediados del siglo XX. A pesar de las ventajas iniciales, los problemas surgidos sobre el espacio urbano, por la naturaleza del modelo de desarrollo turistico utilizado, los dirigen hacia una perdida progresiva de su atractivo turistico. Ante esta circunstancia, se hace necesario intervenir sobre el espacio urbano, no solo para renovar el destino turistico sino tambien para corregir los problemas urbanos generados durante las ultimas decadas en unos municipios que supeditaron sus decisiones exclusivamente a las necesidades turisticas. Una o…
Revisió de mètodes sobre l'ensenyament de la literatura grega i propostes multidisciplinàries en temps de canvis
2012
L'ensenyament de la literatura grega en els estudis de Filologia Clàssica ha abandonat els darrers anys el memorisme tradicional vinculat a un estudi diacrònic i basat en la concatenació de perfils biogràfics dependents de fonts que hom no qüestionava. A més d'incloure el discurs de la moderna teoria literària, l'article present mira de plantejar l'adaptació de la matèria d'acord amb les variables de cada curs i de les modernes tecnologies de treball col·laboratiu en línia.