Assessment of avoidance behaviour by earthworms (Lumbricus rubellus and Octolasion cyaneum) in laboratory-based linear pollution gradients.

Avoidance behaviour by earthworms is recognised as a valuable endpoint in soil quality assessment and has resulted in the development of a standardised test (ISO 17512-1: 2008) providing epigeic earthworms with a choice between test and control soils. This study sought to develop and evaluate an avoidance test utilising soil-dwelling earthworms in linear pollution gradients with Visible Implant Elastomer (VIE) tags used to identify individual organisms. Sequential experiments were established in laboratory-based mesocosms (0.6 m x 0.13 m x 0.1 m) that determined the relative sensitivities (in terms of associated avoidance behaviour) of Octolasion cyaneum and Lumbricus rubellus at varying levels of polluted soil and also assessed the influence of introduction point on recorded movement within gradients. In an initial gradient (0, 25, 50, 75, 100% polluted soil), both species exhibited a clear avoidance response with all surviving earthworms retrieved (after 7 days) from the unpolluted soil. In a less polluted gradient (0, 6.25, 12.5, 18.75, 25%) L. rubellus were retrieved throughout the gradient while O. cyaneum were located within the 0 and 6.25% divisions, suggesting a species-specific response to polluted soil. Results also showed that the use of a linear pollution gradient system has the potential to assess earthworm avoidance behaviour and could provide a more ecologically relevant alternative to the ISO 17512: 2008 avoidance test. However, further work is required to establish the effectiveness of this procedure, specifically in initial chemical screening and assessment of single contaminant bioavailability, where uptake of pollutants by earthworms could be measured and directly related to the point of introduction and retrieval

Hyperoxidation: influence of various oxygen supply levels on oxidation kinetics of phenolic compounds and wine quality

Chenin blanc, Mauzac and Chardonnay musts were hyperoxidized using three different oxygen levels fixed according to the maximum oxygen consumption capacity determined for each must. Phenolic composition of the control and oxidized musts and that of the corresponding wines were analyzed by HPLC. The wines were also submitted to sensory evaluation. Hyperoxidation hardly modified phenolic composition of Chenin blanc and Mauzac musts which were in fact almost totally oxidized after pressing. As well, it induced no change in wine quality in these two varieties. In Chardonnay musts, concentrations of caffeoyl and p-coumaroyl tartaric acid, 2-S-glutathionyl caffeoyl tartaric acid and catechin decreased with increasing oxygen supplies. Wines contained larger amounts of phenolic compounds than musts because part of the quinones formed during oxidation were reduced when sulfiting, especially for intemediate oxygen levels. Thus, sulfiting should be omitted or delayed to allow quinone condensation and maximum efficency of the hyperoxidation technique. Hyperoxidized Chardonnay wines were rated higher in quality and lower in color than the control

Procyanidin composition of Chardonnay, Mauzac and Grenache blanc grapes

Dimer procyanidins, galloylated or not, and trimers were analysed in three white grape varieties: Chardonnay, Mauzac and Grenache blanc. Procyanidins were extracted from the different components of the grape cluster (seeds, stems, skins and pulps) and then quantified by HPLC. Procyanidin B1 is the major component in stems and skins while procyanidin B2 is the major component in seeds

Production of ready to drink red and rosé wines from new seedless grapevine crossbreeds

Monomeric and polymeric flavan-3-ols (proanthocyanidins) content in grapes is higher in seeds compared to berry skins. Monomeric flavan-3-ols are more astringent, however, they can combine with other monomer, with anthocyanins and with mannoproteins released by yeast and therefore lose their harsh features in wines. Proanthocyanidins extracted during fermentation and maceration processes in red wines, are important for the organoleptic characteristics of the product and for its aging. There is a difference between skins and seeds proanthocyanidins, with the latter being perceived as more harsh and astringent. One of the most important purposes of refinement and aging of red wines very rich in polyphenols is the slow loss of bitterness. Instead, for wines ready to drink seeds tannins can give bitter overtones, therefore reducing their quality since consumers generally prefer a reduced astringency and attenuated bitterness. This paper investigates the possibility of employ some new seedless grapes crossings of Vitis vinifera L., obtained in recent breeding programs carried out at the CREA-VE of Turi, for the production of improved red and rosé wines made with traditionally red winemaking

Reversing Gut Damage in HIV Infection: Using Non-Human Primate Models to Instruct Clinical Research

International audienceAntiretroviral therapy (ART) has led to dramatic improvements in the lives of HIV-infected persons. However, residual immune activation, which persists despite ART, is associated with increased risk of non-AIDS morbidities. Accumulating evidence shows that disruption of the gut mucosal epithelium during SIV/HIV infections allows translocation of microbial products into the circulation, triggering immune activation. This disruption is due to immune, structural and microbial alterations. In this review, we highlighted the key findings of gut mucosa studies of SIV-infected macaques and HIV-infected humans that have revealed virus-induced changes of intestinal CD4, CD8 T cells, innate lymphoid cells, myeloid cells, and of the local cytokine/chemokine network in addition to epithelial injuries. We review the interplay between the host immune response and the intestinal microbiota, which also impacts disease progression. Collectively, these studies have instructed clinical research on early ART initiation, modifiers of microbiota composition, and recombinant cytokines for restoring gut barrier integrity

Major CD4 T-Cell Depletion and Immune Senescence in a Patient with Chronic Granulomatous Disease

Chronic granulomatous disease (CGD) results from primary defects in phagocytic reactive oxygen species (ROS) production. T-cell evaluation is usually neglected during patients’ follow-up, although T-cell depletion has been reported in CGD through unknown mechanisms. We describe here a 36-year-old patient with X-linked CGD with severe CD4 T-cell depletion <200 CD4 T-cells/μl, providing insights into the mechanisms that underlie T-cell loss in the context of oxidative burst defects. In addition to the typical infections, the patient featured a progressive T-cell loss associated with persistent lymphocyte activation, expansion of interleukin (IL)-17-producing CD4 T-cells, and impaired thymic activity, leading to a reduced replenishment of the T-cell pool. A relative CD4 depletion was also found at the gut mucosal level, although no bias to IL-17-production was documented. This immunological pattern of exhaustion of immune resources favors prompt, potentially curative, therapeutic interventions in CGD patients, namely, stem-cell transplantation or gene therapy. Moreover, this clinical case raises new research questions on the interplay of ROS production and T-cell homeostasis and immune senescence

The hidden face of wine polyphenol polymerization highlighted by high resolution mass spectrometry

Polyphenols, including tannins and red anthocyanin pigments, are responsible for the color, taste, and beneficial health properties of plant-derived foods and beverages, especially in red wines. Known compounds represent only the emerged part of the "wine polyphenol iceberg". It is believed that the immersed part results from complex cascades of reactions involving grape polyphenols and yeast metabolites. We used a nontargeted strategy based on high-resolution mass spectrometry and Kendrick mass defect plots to explore this hypothesis. Reactions of acetaldehyde, epicatechin, and malvidin-3-O-glucoside, representing yeast metabolites, tannins, and anthocyanins, respectively, were selected for a proof-of-concept experiment. A series of compounds including expected and so-farunknown structures were detected. Random polymerization involving both the original substrates and intermediate products resulting from cascade reactions was demonstrated