Effective use of study-team review techniques in fifth and sixth grade social studies.

Thesis (Ed.M.)--Boston Universit

Metabolites produced by probiotic Lactobacilli rapidly increase glucose uptake by Caco-2 cells

<p>Abstract</p> <p>Background</p> <p>Although probiotic bacteria and their metabolites alter enterocyte gene expression, rapid, non-genomic responses have not been examined. The present study measured accumulation of tracer (2 μM) glucose by Caco-2 cells after exposure for 10 min or less to a chemically defined medium (CDM) with different monosaccharides before and after anaerobic culture of probiotic <it>Lactobacilli</it>.</p> <p>Results</p> <p>Growth of <it>L. acidophilus </it>was supported by CDM with 110 mM glucose, fructose, and mannose, but not with arabinose, ribose, and xylose or the sugar-free CDM. Glucose accumulation was reduced when Caco-2 cells were exposed for 10 min to sterile CDM with glucose (by 92%), mannose (by 90%), fructose (by 55%), and ribose (by 16%), but not with arabinose and xylose. Exposure of Caco-2 cells for 10 min to bacteria-free supernatants prepared after exponential (48 h) and stationary (72 h) growth phases of <it>L. acidophilus </it>cultured in CDM with 110 mM fructose increased glucose accumulation by 83% and 45%, respectively; exposure to a suspension of the bacteria had no effect. The increase in glucose accumulation was diminished by heat-denaturing the supernatant, indicating the response of Caco-2 cells is triggered by as yet unknown heat labile bacterial metabolites, not by a reduction in CDM components that decrease glucose uptake. Supernatants prepared after anaerobic culture of <it>L. gasseri, L. amylovorus, L. gallinarum</it>, and <it>L. johnsonii </it>in the CDM with fructose increased glucose accumulation by 83%, 32%, 27%, and 14%, respectively.</p> <p>Conclusion</p> <p>The rapid, non-genomic upregulation of SGLT1 by bacterial metabolites is a heretofore unrecognized interaction between probiotics and the intestinal epithelium.</p

Transcriptions and Editions for Harp by Carlos Salzedo

Anyone concerned with the harp in this century knows of the genius of Carlos Salzedo. His pedagogical, compositional and professional activities have had a tremendous impact on the harp world. With this in mind, the present study considers his transcriptions for harp from other works and his editings of other composers' harp compositions. It is the purpose of this study to find in what ways his work in this area has been helpful to harpists

Vibrio vulnificus Type 6 Secretion System 1 contains anti-Bacterial properties.

This is the final version of the article. Available from Public Library of Science via the DOI in this record.Vibrio vulnificus is a bacterium responsible for severe gastroenteritis, sepsis and wound infections. Gastroenteritis and sepsis are commonly associated with the consumption of raw oysters, whereas wound infection is often associated with the handling of contaminated fish. Although classical virulence factors of this emerging pathogen are well characterised, there remains a paucity of knowledge regarding the general biology of this species. To investigate the presence of previously unreported virulence factors, we applied whole genome sequencing to a panel of ten V. vulnificus strains with varying virulence potentials. This identified two novel type 6 secretion systems (T6SSs), systems that are known to have a role in bacterial virulence and population dynamics. By utilising a range of molecular techniques and assays we have demonstrated the functionality of one of these T6SSs. Furthermore, we have shown that this system is subject to thermoregulation and is negatively regulated by increasing salinity concentrations. This secretion system was also shown to be involved in the killing of V. vulnificus strains that did not possess this system and a model is proposed as to how this interaction may contribute to population dynamics within V. vulnificus strains. In addition to this intra-species killing, this system also contributes to the killing of inter bacterial species and may have a role in the general composition of Vibrio species in the environment.This work was funded by a CEFAS-Exeter University Alliance PhD Studentship awarded to SRC and SLM. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

The Similkameen Batholith of North-Central Washington and South-Central British Columbia: The Petrotectonic Significance of an Alkaline/Calc-Alkaline Magmatic Complex

The Similkameen batholith is a 170 Ma plutonic complex that contains coeval mafic alkaline and granitic calc-alkaline assemblages. The marginal mafic alkaline suite is silica-undersaturated, characteristically potassic in composition and comprised of malignite, shonkinite, and mafic syenites (+/- nepheline) with biotite and amphibole-bearing pyroxenite cumulates. The granitic plutons of the core are calc-alkaline, I-type, ranging from monzonite to granodiorite to granite in composition. Structural and petrofabric studies indicate that the mafic alkaline suite was intuded and deformed by the calc-alkaline granitoids. Magmatic fabrics within the mafic rocks are concentric to the lithologic zonations and have been overprinted by sub-magmatic flow deformation induced by diapiric emplacement of the core. There is no evidence within the batholith for regional deformation associated with the collision of Quesnellia and North America. Major and trace element variations as well as Sr-isotopic data indicate that the alkaline and calc-alkaline suites are not related by crystal fractionation. However, crystal fractionation appears to have been the dominant process responsible for major element variations within the mafic alkaline suite. Fractionation of the hydrous assemblage clinopyroxene +/- biotite +/- amphibole + apatite + magnetite accounts for compositional variations within the alkaline suite. Calculated modal abundances of the fractionated mineral phases closely approximates observed modal abundances within the pyroxenites, which supports a crystal accumulation origin for the ultramafic rocks. The alkaline and calc-alkaline suites exhibit a geochemical signature characteristic of subduction-related magmatism. Both suites are enriched in alkali and alkaline earth elements and depleted in high field strength elements. Major and trace element compositions of the mafic alkaline suite are consistent with partial melting of a garnet and phlogopite-bearing peridotite source. However, trace element variations within the alkaline suite demonstrate derivation from a chemically heterogeneous mantle-source. The malignite series contains incompatible element ratios consistent with a depleted MORB-type source, whereas the shonkinite series appears to be enriched, indicative of an OIB-type source. The Ba-enrichments of the malignites relative to the shonkinites probably reflect variations in source mineralogy, i.e., greater amounts of phlogopite in the source, not contamination by pelagic sediments. Furthermore, the low variability of initial-Sr ratios (0.7037-0.7042) indicates contamination of the Similkameen magmas by continental crust was relatively minor. Variable degree partial melting of a lower crustal mafic granulite source could produce the incompatible element, REE, and isotopic abundances observed within the calc-alkaline granitoids. Subduction and plate tectonic processes prior to 170 Ma variably enriched (metasomatized) portions of the lithospheric mantle wedge below the western edge of the North American craton. Derivation from this heterogeneous, metasomatized mantle- source resulted in the variably enriched nature of the mafic rocks. The granitoid magmas were the probable result of partial melting related to ponding of hot, hydrous mafic magmas of the alkaline suite at the lower crust-mantle boundary

Site and mechanism of enhanced gastrointestinal absorption of aluminum by citrate

Site and mechanism of enhanced gastrointestinal absorption of aluminum by citrate. Clinical and experimental studies have shown that citrate markedly enhances the intestinal absorption of aluminum (Al), but the site and mechanism of enhanced absorption are unknown. To determine where in the gastrointestinal tract aluminum citrate (Alcitr) was absorbed, Alcitr was gavaged with D-[1-3H] glucose in male Sprague-Dawley rats. Plasma Al levels increased rapidly and simultaneously peaked with D-[1-3G] glucose, suggesting early proximal bowel absorption. In in vitro duodenal and jejunal everted gut preparations, Alcitr incubation resulted in increased tissue Al levels and markedly enhanced transmural transport of Al and citr. Unlike citr, the transmural movement of Al was independent of temperature (37°C vs. 4°C). On the other hand, Al lactate (al Lac) increased tissue associated Al levels but had no effect on transmural Al movement. To determine if this large flux of Al following Alcitr administration was due to paracellular movement, ruthenium red and Ussing chamber studies were used to evaluate the morphologic and functional integrity of cellular tight junctions. Alcitr, as opposed to A1C13, markedly increased ruthenium red deposits in intercellular spaces, especially around goblet cells, and induced a prolonged significant reduction in transmural resistance. Alcitr also resulted in rapid and nearly complete (99.7%) chelation of free calcium, an event known to disrupt cellular tight junction integrity. Taken together, these data suggest that enhanced Al absorption following administration of Alcitr occurs in the proximal bowel via the paracellular pathway due to the opening of cellular tight junctions

第1104回千葉医学会例会・千葉大学大学院医学研究院腫瘍内科学例会

Spreadsheet of data for histology measurements. (XLSX 23 kb

Glucose transport by epithelia prepared from harvested enterocytes

Transformed and cultured cell lines have significant shortcomings for investigating the characteristics and responses of native villus enterocytes in situ. Interpretations of results from intact tissues are complicated by the presence of underlying tissues and the crypt compartment. We describe a simple, novel, and reproducible method for preparing functional epithelia using differentiated enterocytes harvested from the small intestine upper villus of adult mice and preterm pigs with and without necrotizing enterocolitis. Concentrative, rheogenic glucose uptake was used as an indicator of epithelial function and was demonstrated by cellular accumulation of tracer 14C d-glucose and Ussing chamber based short-circuit currents. Assessment of the epithelia by light and immunofluorescent microscopy revealed the harvested enterocytes remain differentiated and establish cell–cell connections to form polarized epithelia with distinct apical and basolateral domains. As with intact tissues, the epithelia exhibit glucose induced short-circuit currents that are increased by exposure to adenosine and adenosine 5′-monophosphate (AMP) and decreased by phloridzin to inhibit the apical glucose transporter SGLT-1. Similarly, accumulation of 14C d-glucose by the epithelia was inhibited by phloridzin, but not phloretin, and was stimulated by pre-exposure to AMP and adenosine, apparently by a microtubule-based mechanism that is disrupted by nocodazole, with the magnitudes of responses to adenosine, forskolin, and health status exceeding those we have measured using intact tissues. Our findings indicate that epithelia prepared from harvested enterocytes provide an alternative approach for comparative studies of the characteristics of nutrient transport by the upper villus epithelium and the responses to different conditions and stimuli