Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 5 de 5
Filter
Add more filters










Database
Language
Publication year range
1.
Oecologia ; 202(1): 175-191, 2023 May.
Article in English | MEDLINE | ID: mdl-37204497

ABSTRACT

Phylogenetically closely related plant species often share similar trait states (phylogenetic signal), but local assembly may favor dissimilar relatives and thereby decouple the diversity of a trait from the diversity of phylogenetic lineages. Associated fauna might either benefit from plant trait diversity, because it provides them complementary resources, or suffer from it due to dilution of preferred resources. We hence hypothesize that decoupling of trait and phylogenetic diversity weakens the relationship between the plant-trait diversity and the abundance and diversity of associated fauna. Studying permanent meadows, we tested for combined effects of plant phylogenetic diversity and diversity of two functional traits (specific leaf area, leaf dry matter content) on major groups of soil fauna (earthworms, mites, springtails, nematodes). We found that only in phylogenetically uniform plant communities, was uniformity in the functional traits associated with (i) high abundance in springtails, and (ii) high abundance of the sub-group that feeds more directly on plant material (in springtails and mites) or those that are more prone to disturbance (in nematodes), and (iii) high diversity in all three groups tested (springtails, earthworms, nematodes). Our results suggest that soil fauna profits from the resource concentration in local plant communities that are uniform in both functional traits and phylogenetic lineages. Soil fauna would hence benefit from co-occurrence of closely related plants that have conserved the same trait values, rather than of distantly related plants that have converged in traits. This might result in faster decomposition and a positive feedback between trait conservatism and ecosystem functioning.


Subject(s)
Ecosystem , Soil , Phylogeny , Plants , Plant Leaves
3.
Waste Manag ; 22(2): 215-28, 2002.
Article in English | MEDLINE | ID: mdl-12003151

ABSTRACT

In 1995, the ADEME launched a research program called "Waste Ecocompatibility" in order to define a reliable methodology for measuring the impact of waste in storage or reuse scenarios. The French concept of "Ecocompatibility" is defined as the situation where the pollutant flux from waste disposed of or used in specified conditions is compatible with the environmental acceptance of the receiving environments. The chief feature of this definition is to integrate the evaluation of the three following terms: pollutants emission from the waste, transport of the pollutants from the waste to the receptor cells and the environmental acceptance of the receiving environments. The "Waste Ecocompatibility" program consisted of a literature survey and an experimental part. The literature study aimed to determine factors and waste characteristics to be considered for a reliable ecocompatility assessment, to provide an overview of the available tools for measuring those factors and characteristics and to propose a first approach of the methodology. In the framework of the experimental program, this approach was then applied to three theoretical scenarios to validate the laboratory tools (comparative study of laboratory and field results) and to calibrate the global methodology. This paper deals with the results of the experimental program concerning the impact study on receiving environments: impact on plants and microorganisms living in soil, impacts on soil fauna and aquatic fauna. In other papers we intend to present the operational methodology for the assessment of waste ecocompatibility. It includes bio-assays at laboratory scale (microcosms), pilot scale (mesocosms) and in situ experiments (experimental prairie). To limit the use of in situ experiments other research works are necessary to validate bio-assays at laboratory or pilot scale.


Subject(s)
Conservation of Natural Resources , Ecosystem , Models, Theoretical , Refuse Disposal , Animals , Forecasting , Soil Microbiology , Soil Pollutants/adverse effects , Water Pollutants/adverse effects
4.
Ann Med Interne (Paris) ; 147 Suppl 1: 18-21, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8952754

ABSTRACT

Phospholipid dependent antibodies are usually measured with assays for antiphospholipid/anticardiolipin antibodies (aPLA) or for lupus anticoagulant (LA) activity. Most of them are targeted to complexes of beta 2-glycoprotein I (beta 2-GPI) and anionic phospholipids (PLP) or to prothrombin for some LA. New understandings allow a better standardisation and optimisation of assays' reactivity. Antigenic targets of phospholipid dependent antibodies were studied on plasmas from 38 patients with the antiphospholipid syndrome (APS) and presenting aPLA and/or LA. Using human beta 2-GPI-PLP complexes as solid phase antigen offers the highest sensitivity for measuring aPLA. Many aPLA, but not all, also react with beta 2-GPI coated on solid phase, however there is no evidence until now that this latter reactivity shows a closest association with the clinical context. Most of the patients with LA present an immunological reactivity to beta 2-GPI alone or to prothrombin, when these proteins are coated on solid phase. In two cases there was a reactivity to only beta 2-GPI-PLP complexes. For the various immunoassays, using NUNC type I plates offers a good binding capacity for coating antigens. They are then present at enough density on solid phase for insuring an efficient binding of autoantibodies. This is an important factor for assay sensitivity and reproducibility. Interestingly, in 1 case with LA, autoantibodies were reactive with coated beta 2-GPI alone but not with its PLP-complexes. In another case reactivity to beta 2-GPI was much higher than that to beta 2-GPI-PLP.


Subject(s)
Antibodies, Antiphospholipid/analysis , Antiphospholipid Syndrome/immunology , Immunoassay/methods , Antibodies, Antiphospholipid/classification , Antibodies, Antiphospholipid/immunology , Antibody Specificity , Glycoproteins , Humans , Lupus Coagulation Inhibitor/analysis , Prothrombin , Reproducibility of Results , Sensitivity and Specificity , beta 2-Glycoprotein I
5.
Haemostasis ; 24(3): 191-203, 1994.
Article in English | MEDLINE | ID: mdl-7527366

ABSTRACT

Presence of beta 2 Glycoprotein I (beta 2GPI), in addition to phospholipids, is an absolute requirement for binding APA. This binding is frequently observed with beta 2GPI coated alone, however many APA react only with beta 2GPI complexed to phospholipids, but not with phospholipids alone. We demonstrate that a subgroup of rabbit polyclonal antibodies to human beta 2GPI binds to this protein only when it is coated on a solid surface, but not if it is in solution. In addition, beta 2GPI present in goat serum is strongly fixed by the coated phospholipids and the complexes formed bind as well APA as the rabbit antibodies to beta 2GPI. The diluent used for testing APA, has a strong incidence on APA's reactivity as it can be a source of beta 2GPI. Antibody binding to beta 2GPI, Prothrombin, Protein S, and Annexin V, coated in the presence or in the absence of phospholipids, was tested in 55 patients with the antiphospholipid syndrome. The strongest binding of antibodies was observed in 39 plasma to a mixture of phospholipids and purified human beta 2GPI, however 17 samples also presented a significant reactivity to beta 2GPI alone. Nine plasmas contained antibodies to Prothrombin, 4 to Protein S, 3 to Annexin V, and 1 to Protein C. We conclude that most of the APA are directed to a complex of beta 2GPI and phospholipids although in some patients antibodies to beta 2GPI alone or to other phospholipid binding proteins are present.


Subject(s)
Antibodies, Antiphospholipid/analysis , Enzyme-Linked Immunosorbent Assay/standards , Glycoproteins/metabolism , Animals , Annexin A5/immunology , Annexin A5/metabolism , Antibody Specificity , Antiphospholipid Syndrome/blood , Antiphospholipid Syndrome/immunology , Autoimmune Diseases/blood , Autoimmune Diseases/immunology , Cattle , Dose-Response Relationship, Immunologic , Enzyme-Linked Immunosorbent Assay/methods , Goats/blood , Humans , Myelin Proteins/metabolism , Myelin Proteolipid Protein , Protein Binding , Protein C/immunology , Protein C/metabolism , Protein S/immunology , Protein S/metabolism , Prothrombin/immunology , Prothrombin/metabolism , Rabbits , Reference Standards , Serum Albumin, Bovine/metabolism , beta 2-Glycoprotein I
SELECTION OF CITATIONS
SEARCH DETAIL
...