Fisiologia dels cecs de pollastre

The morphology and physiology of the chicken cecum is reviewed. The large intestine of the chicken is formed by the rectum and the cloaca, and two well developed ceca, which are two blind sacs, tubular in shape, that originate at the junction of the small intestine and the rectum. Light microscopy observation of the epithelium demonstrates that the proximal region has well developed villi, in contrast to distal cecum where they are either small or absent. Information hitherto available on the physiological mechanisms underlying the filling and emptying of the cecurn has been revised, and it is particularly worthy of note that cecum contents may have both ileal and rectal origins. Several functions have been suggested for the cecum of the chicken but much remains to be discovered about its real physiological significance. There is evidence that proteins and complex carbohydrates can be partially digested in the ceca. It is also claimed that the cecum is the site of production of significant amounts of free volatile fatty acids and vitamins, among other compounds. Several authors have observed absorption of electrolytes and water in the cecum. Urine can enter the ceca by a retrograde flux, which suggests that the cecal epithelium plays a role in osmoregulation in fowl, a function which may be of special relevance in dehydrated animals. Recent reports on the sugar-transport characteristics of the chicken cecum indicate that the epithelium of the proximal area possesses an active transport system as efficient as that described in the small intestine. This raises the possibility that ceca are significant in chicken nutrition, since sugar uptake can occur both during cecal filling and emptying. The physiological role of chicken ceca is not well understood. However, it has been shown that ceca are not essential for animal survival, at least in environmental conditions allowing normal feeding and hydration

Morfologia de l'intestí de pollastres inoculats amb salmonella enteritidis i alimentats amb una dieta suplementada amb un producte ric en β-galactomannans

El consum de productes avícoles contaminats amb Salmonella enterica serovar Enteritidis (Salmonella) és la principal causa de salmonel·losi en humans. Per tal de disminuir l'elevada prevalença de Salmonella en animals de granja, s'està estudiant la inclusió de β-galactomannans en les dietes. L'objectiu d'aquest treball ha estat determinar l'efecte del Salmosan® (1 g/ kg, suplement nutricional procedent de la goma de garrofí rica en β-galactomannans) sobre la morfologia de l'epiteli intestinal de l'ili i de la tonsil·la cecal de pollastres inoculats amb Salmonella per microscòpia electrònica de rastreig. Els resultats s'han comparat amb els obtinguts amb les parets cel·lulars de Saccharomyces cerevisiae (0,5 g/kg) amb activitat prebiòtica demostrada i amb l'antibiòtic colistina (0,5 g/kg del dia 5 a l'11). Les imatges demostren que el Salmosan® i les parets de Saccharomyces cerevisiae redueixen la presència de bacteris adherits a l'epiteli i mantenen, a diferència de la colistina, la integritat de la mucosa. També s'ha observat un increment de les cèl·lules caliciformes i la conseqüent producció de moc. Així, doncs, la utilització de Salmosan® constitueix una bona estratègia per tal de controlar i prevenir la contaminació per Salmonella en productes avícoles destinats al consum humà.The consumption of poultry products contaminated with Salmonella enterica serovar Enteritidis (Salmonella) is the leading cause of salmonellosis in humans. In order to reduce the high prevalence of Salmonella in farm animals, the addition of β-galactomannans to their diet is under study. The aim of this research was to determine by scanning electron microscopy the effect of Salmosan® (1 g/kg), a nutritional supplement produced from β-galactomannan-rich locust bean gum, on the morphology of the intestinal epithelium of the ileum and the caecal tonsil in chickens inoculated with Salmonella. The results were compared to those obtained with Saccharomyces cerevisiae cell walls (0.5 g/kg) possessing proven prebiotic activity, and with the antibiotic colistin (0.5 g/kg, from day 5 to 11). The images show that Salmosan® and Saccharomyces cerevisiae cell walls reduce the presence of bacteria attached to the epithelium and maintain, unlike colistin, the integrity of the mucous membrane. We also observed an increase in goblet cells and the resulting production of mucus. Thus, the use of Salmosan ® is a good strategy to control and prevent Salmonella contamination in poultry products intended for human consumption.El consumo de productos avícolas contaminados con Salmonella enterica serovar Enteritidis (Salmonella) es la principal causa de salmonelosis en humanos. Para disminuir la elevada prevalencia de Salmonella en animales de granja, se está estudiando la inclusión de β-galactomananos en las dietas. El objetivo de este trabajo ha sido determinar el efecto de Salmosan® (1 g/kg, suplemento nutricional procedente de la goma de garrofín rica en β-galactomananos) sobre la morfología del epitelio intestinal del íleon y de la amígdala cecal de pollos inoculados con Salmonella por microscopía electrónica de barrido. Los resultados se han comparado a los obtenidos con las paredes celulares de Saccharomyces cerevisiae (0,5 g/kg) con actividad prebiótica demostrada, y con el antibiótico colistina (0,5 g/kg del día 5 al 11). Las imágenes demuestran que el Salmosan® y las paredes de Saccharomyces cerevisiae reducen la presencia de bacterias adheridas al epitelio y mantienen, a diferencia de la colistina, la integridad de la mucosa. También se ha observado un incremento de las células caliciformes y la consecuente producción de moco. Así pues, la utilización de Salmosan® constituye una buena estrategia para controlar y prevenir la contaminación por Salmonella en productos avícolas destinados al consumo humano

Efecte d'ionòfors de calci i d'AMPc sobre el transport de galactosa

Tesi de Llicenciatura per a la obtenció del Grau de Farmàcia. Facultat de Farmàcia. Universitat de Barcelona. Director: Joana M. Planas i Rosselló. 1981.Els nutrients no electrolítics travessen l'epiteli intestinal fonamentalment per dos mecanismes: la difusió simple i el transport actiu. En les fases iniciáls del desenvolupament, tant en mamífers com en aus, la zona mitjana de l'intestí prim presenta dues característiques importants. En primer lloc, la seva capacitat per a transportar activament sucres i aminoácids es troba molt augmentada, comparada amb la que es presenta en l'animal adult. En segon lloc, el transport actiu és dependent de la concentració del calci extern, dependencia que tampoc s'observa en els adults

La medición de eficiencia general de los equipos para mejorar la productividad en la línea de producto congelado choclo entero de la empresa Lamas Import Export S.A.C Los Olivos -2016

La presente investigación tiene como propósito mejorar la productividad mediante la aplicación de la medición de eficiencia general de los equipos para mejorar la productividad en la línea de producto congelado choclo entero de la empresa Lamas Import Export S.A.C. Los Olivos 2016. La medición de la eficiencia general de los equipos ayuda a gestionar y mejorar el mantenimiento preventivo de las maquinarias, para lograr mayor eficiencia en la producción. Para lo cual se realizó un estudio general de todos los equipos existentes que intervienen en la producción de choclo congelado, encontrando el equipo de congelación de choclo con problemas de cuello de botella, al cual se hizo un seguimiento continuo durante la investigación, aplicando las herramientas necesarias y controlando los parámetros de estudio para la solución de problemas los cuales fueron: análisis con el diagrama de Ishikawa, análisis de Pareto, diagrama de análisis del proceso, cálculo de la capacidad instalada, cálculo del OEE con los indicadores de disponibilidad de la maquinaria, tiempo de ejecución de tareas, productividad de mano de obra y calidad de los productos con la finalidad de mejorar la productividad de la línea de choclo entero congelado. El presente estudio tiene un enfoque cuantitativo que tiene como característica la recolección de datos para probar la hipótesis con base en la medición numérica y el análisis estadístico para establecer los resultados, el diseño de Investigación aplicado es cuasi experimental de tipo correlacional. En Conclusión en base a la medición de eficiencia general de los equipos realizada se aplicó la mejora en la línea de proceso realizando la innovación del material de congelación, con el mantenimiento preventivo del equipo e implementando el área de producción con las herramientas de medición de tiempos y temperaturas, lo cual permitió un incremento en el índice de productividad de 20% entre los meses de Mayo – agosto 2015

Monocarboxylate transporter 1 mediates DL-2-hydroxy-(4-methylthio)butanoic acid transport across the apical membrane of Caco-2 cell monolayers.

The methionine hydroxy analogue DL-2-hydroxy-(4-methylthio)butanoic acid (DL-HMB) is a supplementary source of methionine commonlyadded to commercial animal diets to satisfy the total sulfur amino acid requirement. In this study, we characterized DL-HMB transport acrossthe apical membrane of Caco-2 cells to identify the transport mechanism involved in the intestinal absorption of this methionine source. DLHMBtransport induced a significant decrease in intracellular pH (pHi) and was inhibited in the presence of the protonophore carbonyl cyanide 4-(trifluoromethoxy)-phenylhydrazone. Moreover, both Na1 removal and 5-(N-ethyl-N-isopropyl)amiloride, an inhibitor of apical Na1/H1 exchanger(NHE3), significantly reduced substrate uptake and pHi recovery, suggesting cooperation between H1-dependent DL-HMB transport and NHE3activity. cis-Inhibition experiments with L-Ala, b-Ala, D-Pro, betaine, or glycyl-sarcosine excluded the participation of systems proton amino acidtransporter 1 and peptide transporter 1. In contrast, a-cyano-4-hydroxycinnamate, phloretin, L-lactate, b-hydroxybutyrate, butyrate, andpyruvate, inhibitors and substrates of monocarboxylate transporter 1 (MCT1), significantly reduced DL-HMB uptake. Dixon plot analysis of Llactatetransport in the presence of DL-HMB revealed a competitive interaction (inhibition constant, 17.5 6 0.11 mmol/L), confirming theparticipation of system MCT1. The kinetics of DL-HMB uptake was described by a model involving passive diffusion and a single low-affinity,high-capacity transport mechanism (KD, 1.9 nL/mg protein; Km, 13.16 0.04 mmol/L; and Vmax, 43.6 6 0.14 pmol/mg protein) compatible withMCT1 kinetic characteristics. In conclusion, the methionine hydroxy analogue is transported in Caco-2 cell apical membrane by a transportmechanism with functional characteristics similar to those of MCT1.</p

Flame structure modeling in forest fires

This work in progress presentation wants to summarize the work done in flame modeling applied so far to forest fires and to present the on-going efforts at empirical and physical level that CERTEC is devoting to reach in a near future the goals set in this subject. We are distinguishing here two different approaches depending on whether flame modeling is based on spreading fires or on stationary fires.Peer ReviewedPostprint (published version

Loss of intestinal epithelial barrier function in Salmonella Enteritidis infection

Podeu consultar el llibre complet a: http://hdl.handle.net/2445/63704Intestinal infection with Salmonella enterica serotype Enteritidis, a food-borne infection spread to humans especially through contaminated eggs and egg-products as well as undercooked contaminated fresh meat, is the most common cause of intestinal inflammation in the European Union. Enteritis caused by Salmonella Enteritidis is characterized by fever, diarrhoea and abdominal pain. The disruption of the intestinal epithelial barrier function contributes to diarrhoea and is responsible for the perpetuation of the inflammatory process. In this sense, oxidative stress and the proinflammatory cytokines TNF-α, IFN-γ and IL-1β are described to induce the disorganization of the tight junctions (TJ), the most apical epithelial intercellular junctions and responsible for the paracellular permeability. The interest of this chapter relies not only in the investigation dealing with the mechanisms of TJ regulation but also in the contribution to the development of new tools for the prevention of epithelial barrier disruption in enteritis caused by Salmonella Enteritidis

Cyperus esculentus L. Tubers (Tiger Nuts) Protect Epithelial Barrier Function in Caco-2 Cells Infected by Salmonella Enteritidis and Promote Lactobacillus plantarum Growth

Cyperus esculentus L. tubers (tiger nuts) contain different compounds with several intestinal health-promoting properties. Here, we studied the capacity of tiger nuts from Valencia, Spain, to prevent epithelial barrier function disruption induced by Salmonella enteritidis in Caco-2 cell cultures. Paracellular permeability was assessed by transepithelial electrical resistance (TER) and tight junction protein immunolocalization. Moreover, the effect of tiger nuts on S. enteritidis agglutination, oxidative stress, and Lactobacillus plantarum growth was tested. Compared to controls, tiger nuts partially restored TER in S. enteritidis-infected cultures, an effect confirmed by immunolocalization of tight junction proteins ZO-1 and occludin. The results also revealed that this protective effect may be associated with the capacity to agglutinate the pathogen, restore TER in TNF -stimulated cultures, and reduce reactive oxygen species in H2O2-stimulated cultures. Moreover, they favor L. plantarum growth. In conclusion, this study demonstrates that the tiger nut protects epithelial barrier function by reducing bacterial invasion, along with counteracting TNF and H2O2 effects, thus giving an additional value to this tuber as a potential functional food