RESUMEN
Although laboratories have tried to synthesize new local anesthetics, currently available local anesthetics rarely provide prolonged regional blockade. New models of sustained-release preparations of local anesthetics with liposomes and microspheres have been studied to prolong the duration of the effects of the local anesthetics. In the present study, we examined whether a complex of a branched cyclodextrin (CD), 6-O-alpha-D-maltosyl-beta-cyclodextrin (G2-beta-CD) and lidocaine could prolong local nerve block when compared with plain lidocaine. The sciatic nerve in male Sprague-Dawley rats was blocked with plain lidocaine (n = 10), the complex of G2-beta-CD + lidocaine (n = 10), or plain G2-beta-CD (n = 4). Sensory block was assessed with a hotplate set at 56 degrees C. The median duration of the block was longer in the complex group than in the plain lidocaine group (110 min; range, 70-150 min vs 55 min; range, 40-80 min; P < 0.05), thus demonstrating that the complex with CyD significantly prolonged the nerve block effect of lidocaine. In conclusion, the present study showed that this encapsulating technique with CyD is useful to expand local anesthetic effect in peripheral nerve blockade.
Asunto(s)
Anestésicos Locales , Lidocaína , Bloqueo Nervioso , Nervios Periféricos/efectos de los fármacos , beta-Ciclodextrinas , Animales , Preparaciones de Acción Retardada , Portadores de Fármacos , Composición de Medicamentos , Masculino , Dimensión del Dolor/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , beta-Ciclodextrinas/químicaRESUMEN
The antitumor activity of newly developed taxoids possessing a sugar moiety (glucose, galactose or mannose) to improve water solubility was evaluated. Galactose-bound taxoid (10-alpha-GAG-DT) proved superior to all other taxoids in both water solubility and antitumor activity. Therapeutic efficacy of 10-alpha-GAG-DT in terms of in vivo antitumor activity was found to be approximately equivalent to that of docetaxel, which is known to be superior to that of paclitaxel. The observation that the sugar moiety was gradually hydrolyzed in serum to release docetaxel indicates that 10-alpha-GAG-DT acts as a prodrug.
Asunto(s)
Antineoplásicos Fitogénicos , Taxoides/farmacología , Animales , Peso Corporal/efectos de los fármacos , Fenómenos Químicos , Química Física , Docetaxel , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Indicadores y Reactivos , Leucemia P388/tratamiento farmacológico , Masculino , Ratones , Solubilidad , Taxoides/química , AguaRESUMEN
This study determined the effect of long-term administration of 4(G)-beta-D-galactosylsucrose (lactosucrose; LS) on intestinal calcium absorption. In a randomized, single-blind, parallel-group study, LS (n=9, 6.0 g twice daily) or a placebo (maltose; n=8, 6.0 g twice daily) was administered to healthy young women for 92 wk: the study also included a 4-wk post-administration period. All participants completed the study. Dietary nutrient intake; fecal weight, pH, and moisture content; fecal concentrations of short-chain fatty acids (SCFA), putrefactive products, ammonia, and minerals (calcium, magnesium, phosphorus, and iron); and serum calcium and osteocalcin concentrations were measured every 24 wk. Urinary pyridinoline (PYR) and deoxypyridinoline (DPD), and urinary calcium excretion were measured every 12 wk. Significant effects of oligosaccharide treatment, time, and the interaction between oligosaccharide treatment and time were observed for fecal pH, SCFA, ammonia, and putrefactive product values (p<0.05). Fecal pH, ammonia, and putrefactive product values decreased in the LS group, and the fecal SCFA concentration significantly increased during the administration period; these changes were not observed 4 wk post-administration. To examine the mineral balance of calcium, magnesium, and phosphorus in detail, all the participants completed a 6-d mineral balance study, sometime between week 56 and 60 of the longer study. During the mineral balance study, the daily calcium intake was set at 400 mg; all feces and urine were collected each day for 6 d after an 8-d acclimation period. In the balance study, fecal calcium excretion was significantly lower in the LS group than in the placebo group (p<0.05), and apparent calcium absorption and retention, apparent magnesium and phosphorus absorption, and magnesium retention were significantly higher in the LS group than in the placebo group (p<0.05). Our results suggest that the administration of LS produces a long-term enhancement of intestinal calcium absorption in healthy young women with lower than recommended calcium intakes.
Asunto(s)
Calcio/metabolismo , Absorción Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Intestinos/efectos de los fármacos , Tiempo , Trisacáridos/farmacología , Adulto , Aminoácidos/orina , Amoníaco/metabolismo , Antropometría/métodos , Calcio/sangre , Calcio/orina , Dieta/métodos , Ácidos Grasos Volátiles/metabolismo , Heces/química , Femenino , Humanos , Concentración de Iones de Hidrógeno , Minerales/metabolismo , Osteocalcina/sangre , Valores de Referencia , Estudiantes , Factores de Tiempo , Trisacáridos/administración & dosificaciónRESUMEN
The effects of dietary lactosucrose on calcium absorption from the intestine and calcium accumulation in bones were investigated in growing female rats. The apparent calcium-45 ((45)Ca) absorption, residual (45)Ca ratio in the body, and (45)Ca accumulation in the femur and tibia of lactosucrose-supplemented rats were significantly higher than in control rats 24 h after the administration of a (45)CaCl(2) solution.
Asunto(s)
Envejecimiento/fisiología , Calcio/metabolismo , Absorción Intestinal/efectos de los fármacos , Intestino Grueso/efectos de los fármacos , Intestino Grueso/metabolismo , Trisacáridos/farmacología , Animales , Peso Corporal/efectos de los fármacos , Calcio/sangre , Heces , Femenino , Ratas , Ratas Sprague-DawleyRESUMEN
A synthetic beta-thio-fructofuranoside of mercaptoethanol inhibited not only beta-fructofuranosidases but also alpha-glucosidases. The compound was hardly hydrolyzed by the glycosidases. The thio-fructoside competitively inhibited beta-fructofuranosidases from Aspergillus niger, Candida sp., and Saccharomyces cerevisiae, but not Arthrobacter beta-fructofuranosidase at all. Sucrase activity of rat intestinal sucrase/isomaltase complex was also suppressed in the presence of the thio-fructoside. The thio-fructoside showed noncompetitive inhibition toward maltase activity of the rat intestinal enzyme complex and Saccharomyces sp. alpha-glucosidase. Inhibition against the Bacillus stearothermophilus alpha-glucosidase, Rhizopus glucoamylase, and porcine kidney trehalase were more slight than that against these two alpha-glucosidases.