Taurocholate transport by brush border membrane vesicles from different regions of chicken intestine

Taurocholate transport was studied in brush border membrane vesicles (BBMV) isolated from chicken small (duodenum, jejunum, and ileum) and large (proximal cecum and rectum) intestines, using a rapid filtration technique. The purity of the BBMV was verified by the finding that the specific activity of sucrase (a brush border membrane enzyme marker) was severalfold greater in vesicles than corresponding values in mucosal homogenate. The functional integrity of isolated BBMV was evaluated by the uptake of D-glucose, which showed a transient increase in the presence of Na+. A Na+-dependence of taurocholate uptake was shown in BBMV prepared from ileum, cecum, and rectum, as taurocholate transport was transiently increased (accumulation) in the presence of a Na+ gradient between the external medium and intravesicular medium. The magnitude of the accumulation was similar among ileum, cecum, and rectum. In contrast, BBMV prepared from duodenum and jejunum did not show any Na+-dependent taurocholate transport, as the taurocholate uptake was not affected when a Na+ gradient was replaced by a K+ gradient. The use of taurochenodeoxycholate in the incubation medium inhibited Na+-dependent taurocholate transport in the ileum, cecum, and rectum. This study is the first to show the presence of a Na+-dependent bile salt transport in BBMV obtained from chicken ileum, proximal cecum, and rectum

Leucine absorption after jejunoileal bypass in rats

Jejunal and ileal absorption of L-leucine has been studied in rats subjected to jejunoileal bypass and in sham-operated rats, for five minute periods, using a perfusion technique. Aminoacid concentrations were: 1, 2.5, 5, 10 and 25 mM. In sorne experiments methionine was added to determine simple diffusion. The ratio of the active/diffusive components of absorption were calculated at the different luminal aminoacid concentrations in both groups of rats, showing that this ratio was lower in control animal

Folate transport by prawn hepatopancreas brush-border membrane vesicles.

The transport system of folic acid (Pte-Glu) b y brush-borde r membrane vesicles (BBMV ) isolated from prawn (Penaeus japonicm) hepatopancreas , was studied by measuring the uptake of Pte-Glu . This uptake was found to have two components , intravesicular transport and membrane binding . Membrane binding was not affected by the presence of a trans - membrane pH-gradient at a short incubation period . However , a transmembrane pH - gradient increased membrane binding at 6 0 min. The transpor to f Pte-Glu appeared to be carrier-mediated , was stimulated by an inwardly proton gradient (p H 5. 5 outside , 7. 4 inside ) and was unaffected by a sodium-gradient . The relationship between pH gradient-driven Pte-Glu uptake and medium Pte-Glu concentration followed saturating Michaelis-Menten kinetics . Eadie-Hofste e representation of the pH gradient-driven Pte-Glu uptake indicated a single transport system with a Km of 0.3 7 ^ Man d Vmax of 1.06pmol/mg protein/15s . These findings indicate that BBM V isolated from prawn hepatopancreas possesses a Pte - Glu transport system similar to that described in mammalian intestine

Kinetics of Glycylsarcosine Transport by Isolated Chicken Intestinal Epithelial Cells

Kinctics of Glycylsarcosinc (Gly-Sar) uptake by isolated chicken enterocytes was studied by measuring irs intracellular concentration, and by discriminat ing betwccn the saturable and rhe diffusive components of the total uptake. The diffusive component was greater at pH 6.0 than at pH 7.4, and the J max was also increascd by lowering externa!pH, whereas rhe Km remained in the same order of magnitude . Carnosine competitively inhibits Gly-Sar uptake , indicating that both sharc a common transpon system

Utilización del refuerzo positivo como herramienta para la mejora del aprendizaje en la asignatura de Fisiología Celular

Este trabajo describe la actividad docente desarrollada por los profesores de la asignatura de Fisiología Celular de la Facultad de Farmacia, durante el Curso Académico 1997-98, coincidiendo con la implantación del Nuevo Plan de Estudios de la Licenciatura de Farmacia. El desarrollo de la aplicación de la actividad tuvo como objetivo aplicar nuevas estrategias de enseñanza que mejora­sen a) el nivel de participación y motivación de los alumnos en la asignatura a lo largo del curso académico y b) las calificaciones obtenidas por los alumnos. Así mismo, pretendíamos evaluar el proceso de aprendizaje.This work describes the Activity of Teaching Innovation developed by the professors of the subject Cellular Physiology, of the Faculty of Pharmacy, University of Seville, coinciding with the onset of thc New Plan of Studies of Pharmacy, during the academic course 1997-1998. The aim of thc activity was to apply new strategies in teaching to improve: a) the leve! of participation and motivation of the students in the subject throughout the academic course and b) the score obtained by the students. Furthermore, we tried to evaluate the leaming process

Effect of Distal Small Bowel Resection on Bile Salt Absorption in Caecum

It is well known that surgical resection of the small bowel results in adaptive changes in the residual intestine (7, 13, 14). The entero-hepatic circulation of bile saits, which is responsible for main­ taining constant bile salt pool, is also impaired by intestinal resection. Bile salts are largely reabsorbed by an active trans­ port mechanism in the ileum (3, 8), and to a lesser extent by passive diffusion in the jejunum, caecum and colo

Valor pedagógico de prácticas que utlizan la tecnología multimedia en la asignatura de fisiología celular

Coincidiendo con la implantación del Nuevo Plan de Estudios de la Licenciatura de Farmacia durante el Curso Académico 1997-98, los profesores de la asignatura de Fisiología Celular de la Facultad de Farmacia decidimos utilizar programas de ordenador interactivos, basados en la tecnología multimedia, para la enseñanza práctica de la mencionada asignatura. Este trabajo describe dichas prácticas, así como la evaluación del valor pedagógico de las mismas realizada mediante una encuesta al alumnado.The lectures of the Cellular Physiology course (Faculty of Pharmacy) have used interactive multi-media software for teaching Pharmacy students. This work describes the practice lessons and the results of the evaluation of the pedagogic value of this kind of methodology obtained from a student's survey

Risk-adapted treatment of acute promyelocytic leukemia with all-trans retinoic acid and anthracycline monochemotherapy: Long-term outcome of the LPA 99 multicenter study by the PETHEMA Group

A previous report of the Programa de Estudio y Tratamiento de las Hemopatfas Malignas (PETHEMA) Group showed that a risk-adapted strategy combining all-trans retinoic acid (ATRA) and anthracycline monochemotherapy for induction and consolidation in newly diagnosed acute promyelocytic leukemia results in an improved outcome. Here we analyze treatment outcome of an enlarged series of patients who have been followed up for a median of 65 months. From November 1999 through July 2005 (LPA99 trial), 560 patients received induction therapy with ATRA plus idarubicin. Patients achieving complete remission received 3 courses of consolidation followed by maintenance with ATRA and low-dose chemotherapy. The 5-year cumulative incidence of relapse and disease-free survival were 11% and 84%, respectively. These results compare favorably with those obtained in the previous LPA96 study (P=.019 and P=.04, respectively). This updated analysis confirms the high antileukemic efficacy, low toxicity, and high degree of compliance of a riskadapted strategy combining ATRA and anthracycline monochemotherapy for consolidation therapy