Effects of early dietary intervention with a fermentable fibre on colonic microbiota activity and mucin gene expression in newly weaned rats

Colonic microbiota composition and metabolic processes were investigated after modifying the diet immediately post-weaning in rats. Three-week old Sprague–Dawley rats were fed cellulose or inulin diet for 0 day (d), 7 d or 14 d. Real-time PCR quantification showed significantly higher colonic Bifidobacterium spp. in rats fed inulin on d7 and d14. Inulin was effective in increasing the total bacteria, Bacteroides-Prevotella-Porphyromonas group and Faecalibacterium prausnitzii, while decreasing Lactobacillus spp. Higher concentrations of short-chain fatty acids (SCFAs: acetic, butyric and propionic acids), lactic acid and succinic acid were observed in inulin-fed rats. Inulin ingestion altered colonic mucin (MUC)-3 gene expression, and increased the colon crypt depth with more goblet cells per crypt. Significant positive correlations between SCFAs concentrations and MUC3 expression were observed. Dietary supplementation with inulin altered microbiota composition, and their fermentation end-products may have aided in modifying mucin gene expression and morphology in the colon of young rats.     

Prebiotic effects of fermentable carbohydrate polymers may be modulated by faecal bulking of non‐fermentable polysaccharides in the large bowel of rats

This study investigated the impact of supplementary fermentable polysaccharides inulin (a prebiotic) and barley β‐glucan on the large bowel, when consumed against a background high or low intake of mixed non‐starch polysaccharide. Rats were fed for 28 days with diets containing high (15%) and low (5%) background dietary fibre (BDF; cellulose plus sugar beet fibre), with or without 5% supplementary fermentable fibre (SFF; inulin or barley β‐glucan). High‐BDF diets unsupplemented with inulin or barley β‐glucan caused greater improvement than supplemented low‐BDF diets in several parameters linked to gut health: they increased colonic Bifidobacterium spp., butyric acid concentration in the caecum, and colonic crypt depth more than inulin and barley β‐glucan. For these parameters, inulin and barley β‐glucan added little to the effects of the high‐BDF diet alone. Furthermore, by allowing for dilution due to the greater faecal bulk induced by the mixed fibre compared with inulin or barley β‐glucan, the total quantity of butyric acid in the colon of BDF‐fed rats was greatly amplified. Interpretation of the effects of prebiotics in diets containing dietary fibre requires concurrent analysis of the multiple effects of non‐fermentable bulk.     

Liquid–liquid extraction of Hg(II) from acidic chloride solutions using bis‐2‐ethylhexyl sulfoxide

The liquid–liquid extraction of Hg(II) from acidic chloride solutions has been studied using bis‐2‐ethylhexyl sulfoxide (B2EHSO) as an extractant. For comparison, extraction studies have also been carried out using di‐n‐octyl sulfoxide (DOSO) and diphenyl sulfoxide (DPhSO). The extraction data have been analysed by both graphical and theoretical methods taking into account aqueous phase speciation and all plausible complexes extracted into the organic phase. These results demonstrate that Hg(II) is extracted into xylene as HgCl₂.3R₂SO (where R₂SO represents the sulfoxide). The equilibrium constant of the extracted complex has been deduced by non‐linear regression analysis. The developed liquid–liquid extraction procedure has been applied for the recovery of mercury from the brine‐sludge of a Chlor‐Alkali plant. © 2001 Society of Chemical Industry     

Comparison of functional assay and microarray analysis for determination of Lactobacillus acidophilus LAFTI L10 induced gut immune responses in mice

Probiotics are emerging as functional food supplements that are known to promote specific health benefits beyond basic nutritional functions. The current study evaluated the ability of Lactobacillus acidophilus LAFTI L10 in modulating gut immune responses in mice. Mice were orally fed with L. acidophilus for 14 days, during which they were immunized twice with 10 μg of cholera toxin (CT). The immunoglobulin (Ig)-A response to CT in intestinal fluid and serum were significantly enhanced by L. acidophilus. Mice fed with L. acidophilus increased the number of interferon (IFN)-γ, interleukin (IL)-6 and IL-10 producing cells in the small intestine. Microarray analysis is known to be more sensitive and predictive than functional assays. For this reason, gene expression analysis was chosen as an alternative approach in determining the immunomodulatory effects of L. acidophilus. Gene expression profiles in small intestine of mice fed with L. acidophilus did not uncover the effects related to immune functions that were detected through functional assays. Therefore, functional assays are superior in predicting the immunomodulatory responses of probiotic bacteria.     

Pure and fully texturized Sr2FeMoO6 thin films prepared by pulsed laser deposition from target made with citrate-gel method

Sr₂FeMoO₆ (SFMO) thin films were grown on SrTiO₃ and MgO single crystal substrates by pulsed laser deposition. The SFMO target with nanometer sized grains for the film preparation was made from powder prepared by citrate-gel method. The parameters for ablation were optimized and the importance of the substrate temperature is observed. Film quality was verified with various X-ray diffraction methods and magnetometric measurements. The films are pure, without impurities such as metallic iron, Fe₂O₃, SrMoO₃ or SrMoO₄ and they are completely c-axis oriented. The Curie temperature for the films is higher than room temperature.     

Biorthogonally accessed three-dimensional two-photon memory for relational database operations

Memory bandwidth is a bottleneck for very large database machines. Parallel-access three-dimensional two-photon memories have the potential of achieving enormous throughput (>100 Gbit/s) and capacity (1 Tbit/cm(3)) [Appl. Opt. 29, 2058 (1990)] and, consequently, are well suited for this application. Our analysis shows that some operations can be completed more than 2 orders of magnitude faster with this type of memory than with a system based on serial-access storage. These particular memories have a further feature of being accessible in orthogonal directions. We show that this property, used in conjunction with a three-dimensional data-organization scheme designed for this approach, leads to improved performance by permitting the user a choice of accessing strategies for a given operation.     

MEASUREMENT OF VISCOELASTIC EFFECTS WITH A DEEP CHANNEL SURFACE VISCOMETER

The simple surface fluid represents a class of surface stress-deformation behavior. We develop for this form of material behavior a class of solutions, known as the curvilineal surface flows, that can be analyzed without assuming specific forms for the memory functions. The deep channel surface viscometer and the oscillating deep channel surface viscometer belong to this class of flows.