Cholera toxin promotes the generation of semi-mature porcine monocyte-derived dendritic cells that are unable to stimulate T cells   总被引：2，自引：0，他引：2  

Bimczok D  Rau H  Wundrack N  Naumann M  Rothkötter HJ  McCullough K  Summerfield A 《Veterinary research》2007,38(4):597-612

Cholera toxin (Ctx) is a powerful mucosal adjuvant with potential applications for oral vaccination of swine. Dendritic cells (DC) play a key role in the decision between immunity and tolerance, and are likely target cells for mediating Ctx functions in vivo. Therefore, we examined the capacity of Ctx to enhance stimulatory activity of porcine monocyte-derived DC (MoDC). Ctx promoted the development of a semi-mature DC phenotype, with decreased levels of MHC class II and CD40, but increased CD80/86 expression. These changes were associated with activation of extracellular signal-regulated kinase (ERK), but not NFkappaB or c-Jun N-terminal kinase (JNK). Functionally, Ctx-priming greatly diminished T cell stimulatory capacity both in antigen-specific and superantigen-induced proliferation assays. The lower proliferation rate was not due to increased apoptosis of either DC or T cells. Ctx suppressed TNFalpha secretion by MoDC, but induced IL-10 production. The observed effects on T cell proliferation could only be partially mimicked by IL-10 alone. However, addition of recombinant TNFalpha to co-cultures of Ctx-primed MoDC and lymphocytes restored lymphocyte proliferation in a concentration-dependent manner. Ctx-primed DC were not actively tolerogenic, since they could not suppress proliferative T cell reactions induced by untreated DC.  相似文献   

Identity of mass-flowering crops moderates functional trait composition of pollinator communities     

Beyer  Nicole  Kirsch  Felix  Gabriel  Doreen  Westphal  Catrin 《Landscape Ecology》2021,36(9):2657-2671

Landscape Ecology - Pollinator declines and functional homogenization of farmland insect communities have been reported. Mass-flowering crops (MFC) can support pollinators by providing floral...  相似文献   

Dynamic oxygen mapping in the root zone by fluorescence dye imaging combined with neutron radiography   总被引：1，自引：0，他引：1  

Nicole Rudolph  Hanna G. Esser  Andrea Carminati  Ahmad B. Moradi  André Hilger  Nikolay Kardjilov  Stefan Nagl  Sascha E. Oswald 《Journal of Soils and Sediments》2012,12(1):63-74

Purpose  

The rooted zone of a soil, more precisely the rhizosphere, is a very dynamic system. Some of the key processes are water uptake and root respiration. We have developed a novel method for measuring the real-time distribution of water and oxygen concentration in the rhizosphere as a biogeochemical interface in soil. This enables understanding where and when roots are active in respect to root respiration and water uptake and how the soil responds to it.  相似文献   

Analysis of virgin olive oil volatiles by a novel electronic nose based on a miniaturized SAW sensor array coupled with SPME enhanced headspace enrichment     

García-González DL  Barie N  Rapp M  Aparicio R 《Journal of agricultural and food chemistry》2004,52(25):7475-7479

A novel electronic nose based on solid-phase microextraction (SPME) coupled with a surface acoustic wave (SAW) sensor array has been used to analyze different quality virgin olive oils. A mathematical model was designed with 37 samples to distinguish lampante from the other virgin olive oils categories (extra-virgin and virgin), because lampante-virgin olive oils cannot be consumed without a previous refining process. The model, successfully validated with a test set of 16 samples, was able to classify 90% of the samples correctly. Misclassifications were explained by SPME-HRGC analyses and a second sensory evaluation.  相似文献   

Characterisation of and changes in the atmospheric deposition situation in German forest ecosystems using multivariate statistics     

Nicole?WellbrockEmail author  Winfried?Riek  Barbara?Wolff 《European Journal of Forest Research》2005,124(4):261-271

Based on the results of the atmospheric deposition classification of the year 1989, a methodical approach should be introduced, which—based on the modelled total deposition rates—enables us to characterise the input situation of forest monitoring plots and to delimit load areas in Germany. In 1989, the deposition situation in nearly 1,800 forest monitoring sites (BZE/extensive Soil Condition Inventory) in Germany could be explained by four factors (or three, excluding sea salt impact) with the help of a factor analysis. The factor values were grouped into six deposition types with typical compounds and regional patterns. The classified input rates of the soil inventory plots adequately represent the stress situation and deposition changes in Germany. The application of the statistical approach on the level of Brandenburg clarifies the special local input situation. Due to the special combination of deposed elements, the sources of emissions can be characterised as well. When the soil inventory is repeated, a project planned for 2006, this approach can be used in order to determine homogenous areas for stratified data evaluation.  相似文献   

Concept and feasibility study for the integrated evaluation of environmental monitoring data in forests     

Sabine Augustin  Jan Evers  Hans-Peter Dietrich  Johannes Eichhorn  Thomas Haussmann  Regina Icke  Ansgar Isenberg  Wolfgang Lux  Monica Musio  Hans Pretzsch  Winfried Riek  Thomas Rötzer  Bernd Schultze  Andreas Schulze  Jörg Schröder  Walter Seidling  Nicole Wellbrock  Klaus von Wilpert  Barbara Wolff 《European Journal of Forest Research》2005,124(4):251-260

In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis (crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative, as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.

Sabine AugustinEmail:

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Dietary Esterified Astaxanthin Concentration Effect on Dermal Coloration and Chromatophore Physiology in Spinecheek Anemonefish,Premnas biaculeatus     

Adeljean L. F. C. Ho  Nicole M. Orlando Bertran  Junda Lin 《Journal of the World Aquaculture Society》2013,44(1):76-85

Anemonefishes dominate the marine ornamental aquaculture production and coloration plays an important role in market price of the product. This study examined the effect of dietary esterified astaxanthin concentration and duration on skin coloration in spinecheek anemonefish, Premnas biaculeatus. The chromatophore physiology parameters examined were color, density, and diameter of carotenoid granules. Juveniles of 30 days post hatch (d.p.h.) were fed diets consisting of 23, 214, or 2350 ppm esterified astaxanthin for 115 d and the fish were sampled at 45, 120, and 145 d.p.h. Hue was significantly reduced with increasing time and astaxanthin concentration. Saturation fluctuated over time while luminosity was only affected by time. Carotenoid granule density was similar across the treatments: approximately 0.3 granules/µm². Significant difference in carotenoid granule size was detected, with larger diameters at the higher astaxanthin treatment. Carotenoid granules showed significantly lower hues, higher saturation, and lower luminosity values for the higher astaxanthin concentration diets. This is indicative of higher concentration of carotenoids in the granules. Diets explicitly imparted different coloration in P. biaculeatus and the manifested color differences in the fish are result of increased carotenoid granule size and increased carotenoid concentration within granules. Astaxanthin concentration of 214 ppm imparts adequate coloration for high market value.  相似文献   

Effects of agricultural management on nematode–mite assemblages: Soil food web indices as predictors of mite community composition     

Sara Sánchez-Moreno  Nicole L. Nicola  Howard Ferris  Frank G. Zalom 《Applied soil ecology》2009,41(1):107-117

Biological indicators based on abundances of soil organisms are powerful tools for inferring functional and diversity changes in soils affected by agricultural perturbations. Field plots, combining organic and conventional practices with no tillage, conservation tillage and standard tillage maintained different nematode assemblages and soil food webs. Soil food web indices based on nematode assemblages were reliable predictors of the trophic composition of functional characteristics of soil mite assemblages. Bacterial-feeding and predatory nematodes, together with predatory mites, were abundant in the organic-no till treatments and were associated with high values of the Enrichment and the Structure Index based on nematode assemblages. Conventional-Standard tillage treatments had high abundances of fungal- and plant-feeding nematodes and algivorous mites, associated with high values of the Basal and Channel Index. This study validates the hypothesis that nematode-based soil food web indices are useful indicators of other soil organisms such as mites, with similar functional roles and environmental sensitivities.  相似文献   

Isolation of Cokeromyces recurvatus, initially misidentified as Coccidioides immitis, from peritoneal fluid in a cat with jejunal perforation.     

Cheri Nielsen  Deanna A Sutton  Ilze Matise  Nicole Kirchhof  Melissa C Libal 《Journal of veterinary diagnostic investigation》2005,17(4):372-378

Cokeromyces recurvatus, a zygomycete, was isolated by fungal culture from the peritoneal fluid of a cat with jejunal perforation secondary to intestinal lymphosarcoma. This organism has not been recovered previously from a veterinary patient. The tissue form of C. recurvatus is morphologically similar to those of Coccidioides immitis and Paracoccidioides brasiliensis and may be misdiagnosed as 1 of these organisms on the basis of cytologic or histopathologic specimens, particularly in geographic regions where these organisms are not endemic.  相似文献   

Ultrastructural and cytochemical aspects of silicon-mediated rice blast resistance   总被引：1，自引：0，他引：1  

Rodrigues FA  Benhamou N  Datnoff LE  Jones JB  Bélanger RR 《Phytopathology》2003,93(5):535-546

ABSTRACT Although exogenous application of silicon (Si) confers efficient control of rice blast, the probable hypothesis underlying this phenomenon has been confined to that of a mechanical barrier resulting from Si polymerization in planta. However, in this study, we provide the first cytological evidence that Si-mediated resistance to Magnaporthe grisea in rice correlates with specific leaf cell reaction that interfered with the development of the fungus. Accumulation of an amorphous material that stained densely with toluidine blue and reacted positively to osmium tetroxide was a typical feature of cell reaction to infection by M. grisea in samples from Si+ plants. As a result, the extent of fungal colonization was markedly reduced in samples from Si+ plants. In samples from Si- plants, M. grisea grew actively and colonized all leaf tissues. Cytochemi-cal labeling of chitin revealed no difference in the pattern of chitin localization over fungal cell walls of either Si+ or Si- plants at 96 h after inoculation, indicating limited production of chitinases by the rice plant as a mechanism of defense response. On the other hand, the occurrence of empty fungal hyphae, surrounded or trapped in amorphous material, in samples from Si+ plants suggests that phenolic-like compounds or phytoalexins played a primary role in rice defense response against infection by M. grisea. This finding brings new insights into the complex role played by Si in the nature of rice blast resistance.  相似文献