A role for CD40 expression on CD8+ T cells in the generation of CD8+ T cell memory     

Bourgeois C  Rocha B  Tanchot C 《Science (New York, N.Y.)》2002,297(5589):2060-2063

The delivery of CD4 help to CD8+ T cell responses requires interactions between CD40 and CD40 ligand and is thought to occur through antigen-presenting cell (APC) activation. Here we show that generation of memory CD8+ T cells displaying an enhanced capacity for cell division and cytokine secretion required CD4 help but not CD40 expression by the APCs. Activated CD4+ and CD8+ T cells expressed CD40; and in the absence of this protein, CD8+ T cells were unable to differentiate into memory cells or receive CD4 help. These results suggest that, like B cells, CD8+ T cells receive CD4 help directly through CD40 and that this interaction is fundamental for CD8+ T cell memory generation.  相似文献   

Can germplasm resources be used to increase the ascorbic acid content of stored potatoes?     

Corinne S. Davies  Michael J. Ottman  Stanley J. Peloquin 《American Journal of Potato Research》2002,79(4):295-299

Freshly harvested potato tubers contain up to 50 mg/100g ascorbic acid (AA), but levels decline rapidly during cold storage. Genetic alterations to boost the AA content of stored tubers would contribute to human nutrition and might improve tuber resistance to oxidative damage during chilling. While studying the breeding potential ofSolanum phureja germplasm, we identified a 24-chromosome Phureja-haploid Tuberosum hybrid (clone I, USW5295.7) that retained a twofold higher content of tuber AA than neighboring clones after storage at 5 C. Clone I produces 2n-pollen through a mechanism genetically equivalent to first-division restitution (FDR), which transmits much of the nonadditive genetic variance for tuber yield. We now report a survey of clone I progeny showing significant family and ploidy effects on tuber AA levels during cold storage, consistent with the transmission of information for higher AA by FDR 2n-pollen. These results encourage further study of 2n-gametes and wild species germplasm to breed for increased tuber AA.  相似文献   

Epidemiology,molecular virology and diagnostics of Schmallenberg virus,an emerging orthobunyavirus in Europe     

Virginie Doceul  Estelle Lara  Corinne Sailleau  Guillaume Belbis  Jennifer Richardson  Emmanuel Bréard  Cyril Viarouge  Morgane Dominguez  Pascal Hendrikx  Didier Calavas  Alexandra Desprat  Jér?me Languille  Lo?c Comtet  Philippe Pourquier  Jean-Fran?ois Eléou?t  Bernard Delmas  Philippe Marianneau  Damien Vitour  Stéphan Zientara 《Veterinary research》2013,44(1):31

After the unexpected emergence of Bluetongue virus serotype 8 (BTV-8) in northern Europe in 2006, another arbovirus, Schmallenberg virus (SBV), emerged in Europe in 2011 causing a new economically important disease in ruminants. The virus, belonging to the Orthobunyavirus genus in the Bunyaviridae family, was first detected in Germany, in The Netherlands and in Belgium in 2011 and soon after in the United Kingdom, France, Italy, Luxembourg, Spain, Denmark and Switzerland. This review describes the current knowledge on the emergence, epidemiology, clinical signs, molecular virology and diagnosis of SBV infection.  相似文献   

Nutritional value of faba bean (Vicia faba L.) seeds for feed and food     

Katell Crépon  Pascal Marget  Corinne Peyronnet  Benoit Carrouée  Paolo Arese  Gérard Duc 《Field Crops Research》2010

Faba bean (Vicia faba L.) is a protein-rich legume seed well adapted to most climatic areas of Europe and widely used for feed and food. Even if the seed is generally recognized to be of good nutritional value, existing genetic variability for seed composition offers possibilities for improvement of this trait by breeding. Four major quality types must be distinguished according to the presence or absence of tannins in the integuments and of vicine (V) and convicine (C) in the cotyledons. The nutritional value of diets containing varying amounts of different faba bean cultivars characterized by high or low levels of tannins, and high or low levels of vicine + convicine (VC), has been examined in monogastric animals and ruminants. Low-tannin content generally results in higher protein and energy digestibility for monogastric animals and low VC content has a positive effect on laying hen and broiler production performances. V and C, inactive precursors of divicine and isouramil are redox compounds potentially toxic to human carriers of a widespread genetic deficiency of the erythrocyte (red blood cell, RBC) enzyme glucose-6-phosphate dehydrogenase (G6PD). Ingestion of faba beans by these deficient individuals may cause a severe, potentially lethal hemolytic anemia (favism). The mechanism of action of divicine and isouramil in the G6PD-deficient RBC is discussed.  相似文献   

Composition of hybrid larch (Larix × eurolepis Henry) forest reproductive materials: How much does hybrid percentage affect stand performance?     

Gwenaël Philippe  Corinne Buret  Stéphane Matz  Luc E. Pâques 《New Forests》2016,47(4):541-564

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Co-circulation of bluetongue and epizootic haemorrhagic disease viruses in cattle in Reunion Island     

Sailleau C  Zanella G  Breard E  Viarouge C  Desprat A  Vitour D  Adam M  Lasne L  Martrenchar A  Bakkali-Kassimi L  Costes L  Zientara S 《Veterinary microbiology》2012,155(2-4):191-197

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Mammary gland carcinoma in a dog with peripheral blood and bone marrow involvement associated with disseminated intravascular coagulation     

Jaillardon L  Barthélemy A  Goy-Thollot I  Pouzot-Nevoret C  Fournel-Fleury C 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2012,41(2):261-265

A 7-year-old female Leonberger dog was referred to the National Veterinary School of Lyon Teaching Hospital with a 2-day history of anorexia and bleeding. A mammary mass had been removed 7 months earlier, but histologic examination was not performed. On physical examination, the dog was depressed and had pale mucous membranes and numerous petechiae and hematomas. Significant laboratory findings were moderate thrombocytopenia, prolonged prothrombin, activated partial thromboplastin, and thrombin times, hypofibrinogenemia, and increased concentration of fibrin(ogen) degradation products. A peripheral blood smear, buffy coat preparation, and bone marrow aspirate contained low numbers of large atypical cells that had moderate nuclear:cytoplasmic ratios, oval nuclei with multiple prominent nuclei, and basophilic cytoplasm with villous projections. A small nodule was found in the left inguinal mammary gland, and a fine-needle aspirate contained cells similar to those in blood and bone marrow. In samples of blood, bone marrow, and the mammary mass, the neoplastic cells were immunoreactive for cytokeratin. The diagnosis was mammary carcinoma with secondary disseminated intravascular coagulation (DIC) and disseminated tumor cells in bone marrow and circulating tumor cells in blood; this diagnosis was not confirmed by histopathologic examination. Owing to clinical deterioration and the poor prognosis, the dog was euthanized and a necropsy was not performed. This is the first report of a canine mammary carcinoma with circulating tumor cells and secondary DIC.  相似文献   

Spatial patterns of grasses influence soil macrofauna biodiversity in Amazonian pastures     

Jérôme Mathieu  Michel Grimaldi  Corinne Rouland  Thierry Desjardins 《Soil biology & biochemistry》2009,41(3):586-154

Grasslands are often characterized by small-scale spatial heterogeneity due to the juxtaposition of grass tufts and bare ground. Although the mechanisms generating plant spatial patterns have been widely studied, few studies concentrated on the consequences of these patterns on belowground macrofauna. Our objective was to analyze the impact of grass tuft (Brachiaria bryzantha cv. marandu) spatial distribution on soil macrofauna diversity in Amazonian pastures, at a small scale (less than 9 m²). Soil macrofauna was sampled among B. bryzantha tufts, which showed a variable spatial distribution ranging from dense to loose vegetation cover. The vegetation configuration explained 69% of the variation in total soil macrofauna density and 68% of the variation in total species richness. Soil macrofauna was mainly found in the upper 10 cm of soil and biodiversity decreased with increasing distances to the nearest grass tuft and increased with increasing vegetation cover. The size of the largest grass tuft and the micro-landscape connectivity also had a significant effect on biodiversity. The density and species richness of the three principal soil ecological engineers (earthworms, ants and termites) showed the best correlations with vegetation configuration. In addition, soil temperature significantly decreased near the plants, while soil water content was not influenced by the grass tufts. We conclude that soil macrofauna diversity is low in pastures except close to the grass tufts, which can thus be considered as biodiversity hotspots. The spatial arrangement of B. bryzantha tussocks influences soil macrofauna biodiversity by modifying soil properties in their vicinity. The possible mechanisms by which these plants could affect soil macrofauna are discussed.  相似文献   

Quantification of zearalenone in various solid agroenvironmental samples using D6-zearalenone as the internal standard     

Hartmann N  Erbs M  Wettstein FE  Hoerger CC  Schwarzenbach RP  Bucheli TD 《Journal of agricultural and food chemistry》2008,56(9):2926-2932

Because of its pronounced estrogenicity, zearalenone may be of concern not only in the aqueous but also in the terrestrial environment. Therefore, we developed several analytical methods to quantify zearalenone in different solid matrices of agroenvironmental relevance (i.e., plant organs, soil, manure, and sewage sludge). The use of D(6)-zearalenone as the internal standard (IS) was essential to render the analytical method largely matrix-independent because it compensated for target analyte losses during extract treatment and ion suppression during ionization. Soil and sewage sludge samples were extracted with Soxhlet, whereas plant material and manure samples were extracted by liquid solvent extraction at room temperature. Absolute recoveries for zearalenone were 70-104% for plant materials, 105% for soil, 76% for manure, and 30% for sewage sludge. Relative recoveries ranged from 86 to 113% for all matrices, indicating that the IS was capable to largely compensate for losses during analysis. Ion suppression, between 8 and 74%, was in all cases compensated by the IS but influenced the method quantification levels. These were 3.2-26.2 ng/g(dryweightdw) for plant materials, 0.7 ng/g(dw) for soil, 12.3 ng/g(dw) for manure, and 6.8 ng/g(dw) for sewage sludge. Plant material concentrations varied from 86 ng/g(dw) to more than 16.7 microg/g(dw), depending on the organ and crop. Soil concentrations were between not detectable and 7.5 ng/g(dw), depending on the sampling depth. Zearalenone could be quantified in all manure samples in concentrations between 8 and 333 ng/g(dw). Except for two of the 85 investigated sewage sludge samples, zearalenone concentrations were below quantification limit.  相似文献   

Mast cell and eosinophil mucosal responses in the large intestine of horses naturally infected with cyathostomes     

Collobert-Laugier C  Hoste H  Sevin C  Chartier C  Dorchies P 《Veterinary parasitology》2002,107(3):251-264

From December 1998 to March 2000, caecum and ascendant colon of 42 horses naturally infected with cyathostomes were collected during routine necropsy or from a local slaughterhouse. Changes in the numbers of mucosal and submucosal mast cells (MMC and SMMC), intraepithelial, mucosal and submucosal eosinophils (IE, ME and SME) in the large intestine were investigated by histochemical techniques in relation to the worm burdens. The effect of age was examined in three subgroups: 6-24-month-old horses (group 1), 2-10-year-old horses (group 2) and horses more than 10 years of age (group 3). No globule leucocytes were detected in any sections. No significant variations with breed or sex were observed in cell counts. The main variations were higher eosinophil counts in groups 2 and 3 and a marked increase of the MMC counts in the oldest horses (group 3). For each cell type, the infiltration was homogeneous and generalised along the large intestine. In the whole horse sample, the IE numbers were the only parameters that correlated with the MMC and SMMC counts. Very few significant relationships were found between mast cells and eosinophils in groups 1 and 3, whereas numerous positive correlations were recorded in group 2. In the whole horse sample, several correlations were found between different cell counts and cyathostome burdens. The numbers of larvae, adult worms, and the total worm burdens were related to some of the tissular eosinophil counts while the percentage of early third stage larvae (EL3) was linked to mast cell densities. These relations between cells and worm populations showed variations with age. In group 1, most of the significant associations were found between eosinophil counts (IE and SME) and the total numbers of larvae and worms; in group 2, they were noticed between the three eosinophil types and the total cyathostome burdens. In group 3, a MMC hyperplasia was observed and correlations were mostly recorded between these MMC and the total numbers of adult worms or the percentage of EL3. Several associations were also detected between eosinophils (mainly ME and/or IE) and different cyathostome burdens. These variations in the relationship between inflammatory cells and cyathostomes seemed to be consistent with the cellular changes observed among the three age groups. These results suggest that eosinophil and mast cell infiltrations quantified in the large intestine wall might be associated with cyathostome infection.  相似文献