141 research outputs found

    Growth in brine, at low temperature and different organic acids, of yeasts from table olives

    Get PDF
    The evolution of the main yeast species related to table olives (Pichia anomala, Pichia membranaefaciens, Pichia minuta, Saccharomyces cerevisiae, Candida diddensii, Candida famata, and Debaryomyces hansenii) at low temperature (7ºC) and different physico-chemical brine conditions was studied, using the log of the relative growth as response. In general, the NaCl concentration had a reduced effect, which was slightly greater at pH 3.5, although it was never significant. The effects of pH and type of acid were significant: the presence of acetic acid always diminished the yeast population with time; however the population was maintained, or even slightly increased, in the presence of lactic acid. Such effects were higher at pH 3.5 than at pH 4.0. The behavior of the yeast species was diverse. Sacch. cerevisiae, P. membranaefaciens, C. famata y Deb. hansenii disminished with time in 8% NaCl. The yeast population markedly decreased at pH 3.5, mainly in the case of Sacch. cerevisiae and C. famata. The presence of acetic acid decreased the yeast population in most species and always lead to a progressive diminution of it with time. No differences between species due to lactic acid was observed. These results can be of interest for the development of commercial presentations of table olives to be preserved at low temperature and with a reduced level of sodium.Se ha estudiado la evolución de las principales especies de levaduras relacionadas con las aceitunas de mesa (Pichia anomala, Pichia membranaefaciens, Pichia minuta, Saccharomyces cerevisiae, Candida diddensii, Candida famata , y Debaryomyces hansenii) a baja temperara (7ºC) y en diversas condiciones físico-químicas en las salmueras, utilizando el log del crecimiento relativo como respuesta. En general, la concentración de sal tiene un efecto muy limitado, que se aprecia algo más a pH 4, pero sin llegar a ser significativo. Los efectos del tipo de ácido y pH fueron significativos; la presencia de acético disminuye la población con el tiempo, mientras que con el láctico se mantiene e, incluso, se eleva ligeramente. Estos efectos se acentúan a pH 3,5. El comportamiento de cada levadura frente a las diferentes variables ha sido diverso. La población relativa de las especies Sacch. cerevisiae , P. membranaefaciens , C. famata y Deb. hansenii disminuyó con el tiempo en presencia del 8 % de NaCl. A pH 3,5 disminuye muy sensiblemente la población inicial en todos los casos, siendo tal influencia más destacada en Sacch. cerevisiae y C. famata. La presencia de acético disminuye de forma importante la población inicial inoculada en la mayoría de los casos y provocó siempre un descenso paulatino en las mismas. No se observó diferencias entre las especies debido al ácido láctico. Estos estudios pueden ser de interés para el desarrollo de presentaciones comerciales de aceitunas de mesa refrigeradas y con reducido nivel de sodio.Los autores desean expresar su gratitud a la CICYT (AGL2000-1539-CO2-01) y a la Unión Europea (FAIR-97-9526) por la financiación parcial de esta investigación.Peer reviewe

    Mass spectrometry imaging identifies palmitoylcarnitine as an immunological mediator during Salmonella Typhimurium infection

    Get PDF
    Salmonella Typhimurium causes a self-limiting gastroenteritis that may lead to systemic disease. Bacteria invade the small intestine, crossing the intestinal epithelium from where they are transported to the mesenteric lymph nodes (MLNs) within migrating immune cells. MLNs are an important site at which the innate and adaptive immune responses converge but their architecture and function is severely disrupted during S. Typhimurium infection. To further understand host-pathogen interactions at this site, we used mass spectrometry imaging (MSI) to analyse MLN tissue from a murine model of S. Typhimurium infection. A molecule, identified as palmitoylcarnitine (PalC), was of particular interest due to its high abundance at loci of S. Typhimurium infection and MLN disruption. High levels of PalC localised to sites within the MLNs where B and T cells were absent and where the perimeter of CD169+ sub capsular sinus macrophages was disrupted. MLN cells cultured ex vivo and treated with PalC had reduced CD4+CD25+ T cells and an increased number of B220+CD19+ B cells. The reduction in CD4+CD25+ T cells was likely due to apoptosis driven by increased caspase-3/7 activity. These data indicate that PalC significantly alters the host response in the MLNs, acting as a decisive factor in infection outcome

    Characterization of behavioral, signaling and cytokine alterations in a rat neurodevelopmental model for schizophrenia, and their reversal by the 5-HT₆ receptor antagonist SB-399885

    Get PDF
    Post-weaning social isolation of rats produces neuroanatomical, neurochemical and behavioral alterations resembling some core features of schizophrenia. This study examined the ability of the 5-HT₆ receptor antagonist SB-399885 to reverse isolation-induced cognitive deficits, then investigated alterations in hippocampal cell proliferation and hippocampal and frontal cortical expression of selected intracellular signaling molecules and cytokines. Male Lister-hooded rats (weaned on post-natal day 21-24 and housed individually or in groups of 3-4) received six i.p. injections of vehicle (1% Tween 80, 1 mL/kg) or SB-399885 (5 or 10 mg/kg) over a two week period starting 40 days post-weaning, on the days that locomotor activity, novel object discrimination (NOD), pre-pulse inhibition of acoustic startle and acquisition, retention and extinction of a conditioned freezing response (CFR) were assessed. Tissue was collected 24 h after the final injection for immunohistochemistry, reverse-phase protein microarray and western blotting. Isolation rearing impaired NOD and cue-mediated CFR, decreased cell proliferation within the dentate gyrus, and elevated hippocampal TNFα levels and Cdc42 expression. SB-399885 reversed the NOD deficit and partially normalized CFR and cell proliferation. These effects were accompanied by altered expression of several members of the c-Jun N-terminal Kinase (JNK) and p38 MAPK signaling pathways (including TAK1, MKK4 and STAT3). Although JNK and p38 themselves were unaltered at this time point hippocampal TAK1 expression and phosphorylation correlated with visual recognition memory in the NOD task. Continued use of this neurodevelopmental model could further elucidate the neurobiology of schizophrenia and aid assessment of novel therapies for drug-resistant cognitive symptoms

    Kaart van de twee platte warelds bollen [cartographic material] : waar in aangetoond word alt geen tot heden is ondekt na de Nieuste kaarten getekent /

    No full text
    Double hemispherical map of the world. Australia, called Nieuw Hollande, appears with Botany Bay clearly marked in Nieuw Zd. Walles. Van Diemen's Land is attached to a distorted eastern coastline. Relief shown pictorially.; [Plate 1] from: Nieuwe natuur-geschieden handelkundige zak- en reis-atlas : behelzende eene beknopte beschrijving van de gronden der astronomij ... / Gerrit Brender a Brandis. Amsterdam : N. T. Gravius, [1787?]; Includes tables titled: Dese tafel toont aan hoe veet Uren men regt ooft en West moet reifen and Eer men een graad in langte verandert na t'ooft of Weft op alle pools hoogte. Also includes text titled: Langen der Dagen and Langen der Nachten.; Tooley, 186; Phillips, 660; Also available in an electronic version via the internet at: http://nla.gov.au/nla.map-rm4476
    corecore