Human peripheral basophils extended phenotype shows a high expression of CD244 immuno-regulatory receptor.

Introduction: Basophils play a major physio-pathological role in hypersensitivity related diseases. Basophils express high affinity Immunoglobulin (Ig) E receptors (FcεRI), IgG and complement regulatory. Basophils also have immunoregulatory activity through interaction with T cells.

Microalgal whole-cell biomarkers as sensitive tools for fast toxicity and pollution monitoring of urban wet weather discharges.

Urban wet weather discharge (UWWD) management is an important issue. UWWD often represents a significant source of pollution in all aquatic bodies. The occurrence of this pollution is difficult to predict due to the variability of storm events and the unknown contents of urban watershed leached out by rain.

Xurography-based microfluidic algal biosensor and dedicated portable measurement station for online monitoring of urban polluted samples.

A critical need exists to develop rapid, in situ, and real-time tools to monitor the impact of pollution discharge toxicity on aquatic ecosystems. The present paper deals with the development of a novel, simple-to-use, low-cost, portable, and user-friendly algal biosensor. In this study, a complete and autonomous portable fluorimeter was developed to assess the A-chlorophyll fluorescence of microalgae, inserted by capillarity into low-cost and disposable xurography-based microfluidic chips.

Assessment of long term ecotoxicity of urban stormwaters using a multigenerational bioassay on Ceriodaphnia dubia: A preliminary study.

Standardized ecotoxicity bioassays show some limits to assess properly long-term residual toxicity of complex mixture of pollutants often present at low concentration, such as stormwaters. Among invertebrate organisms used for ecotoxicity testing, the microcrustacean Ceriodaphnia dubia (C. dubia) is considered as one of the most sensitive, especially regarding reproduction impairment as a toxicity endpoint.

Identification and assessment of ecotoxicological hazards attributable to pollutants in urban wet weather discharges.

Urbanization has led to considerable pressure on urban/suburban aquatic ecosystems. Urban Wet Weather Discharges (UWWD) during rainfall events are a major source of pollutants leached onto and into urban surfaces and sewers, which in turn affect aquatic ecosystems. We assessed the ecotoxicity of the different compounds identified in UWWD and identified the hazard represented by each of them.

Methods for evaluating the pollution impact of urban wet weather discharges on biocenosis: A review.

Rainwater becomes loaded with a large number of pollutants when in contact with the atmosphere and urban surfaces. These pollutants (such as metals, pesticides, PAHs, PCBs) reduce the quality of water bodies. As it is now acknowledged that physico-chemical analyses alone are insufficient for identifying an ecological impact, these analyses are frequently completed or replaced by impact studies communities living in freshwater ecosystems (requiring biological indices), ecotoxicological studies, etc.

Feasibility of using a translucid inorganic hydrogel to build a biosensor using immobilized algal cells.

Anthropic activities generate contaminants, as pesticides and other pollutants, in the aquatic environment which present a real threat to ecosystems and human health. Thus, monitoring tools become essential for water managers to detect these chemicals before the occurrence of adverse effects. In this aim, algal cell biosensors, based on photosystem II activity measurement, have been designed for several years in previous studies.

Tamoxifen ecotoxicity and resulting risks for aquatic ecosystems.

Tamoxifen, a drug used to treat cancer, is regularly found in hydrosystems at concentrations of several hundred ng L(-1). To characterize its ecotoxicity, we implemented a battery of bioassays on organisms belonging to 3 different trophic levels: Pseudokirchneriella subcapitata, Chlorella vulgaris and Chlamydomonas reinhardtii, for primary producers, Daphnia magna (immobilization, grazing and reproduction) for primary consumers, and Danio rerio for secondary consumers (embryotoxicity test). In view of the results obtained and the ecotoxicity values of tamoxifen available in the literature, we established a PNEC (Predictive No Effect Concentration) equal to 81 ng L(-1) for continental water.

Co-encapsulation and microalgae in silica matrices, a stepping stone toward a portable microcosm.

We report on the first silica encapsulation of a metazoan (), with a high initial viability (96% of the population remained active 48 h after encapsulation). Moreover, the co-encapsulation of this crustacean and microalgae () was achieved, creating inside a silica monolith, the smallest microcosm developed to present. This artificial ecosystem in a greatly diminished scale isolated inside a silica nanoporous matrix could have applications in environmental monitoring, allowing ecotoxicity studies to be carried out in portable devices for on-line and pollution level assessment.

Rhodamine B doped silica encapsulation matrices for the protection of photosynthetic organisms.

An advanced encapsulation matrix that efficiently protects microalgae from harmful UV light without causing toxicity to the entrapped culture is developed based on the electrostatic adsorption of the dye Rhodamine B on silica preformed particles during sol-gel synthesis. The three microalgae (Chlorella vulgaris, Pseudokirchneriella subcapitata and Chlamydomonas reinhardtii) were previously immobilized in alginate following the Two-step procedure. Once entrapped in the silica gel, Rhodamine B act as an inner cut-off filter, protecting the encapsulated organisms from UV radiation.

Sol-gel silica platforms for microalgae-based optical biosensors.

An advanced hybrid biosensing platform with improved optical quality is developed based on the acidic encapsulation of microalgi in silica matrices synthesized by TAFR (tetraethoxysilane derived alcohol free route). The three microalgi (Chlorella vulgaris, Pseudokirchneriella subcapitata and Chlamydomonas reinhardtii) were previously immobilized in alginate following the two-step procedure. Tuning the alginate protecting function with the aid of Tris-HCl buffer, the sol-gel synthesis was conducted at pH 4.

Development of a biosensor for environmental monitoring based on microalgae immobilized in silica hydrogels.

A new biosensor was designed for the assessment of aquatic environment quality. Three microalgae were used as toxicity bioindicators: Chlorella vulgaris, Pseudokirchneriella subcapitata and Chlamydomonas reinhardtii. These microalgae were immobilized in alginate and silica hydrogels in a two step procedure.

Ecotoxicological risk assessment linked to infilling quarries with treated dredged seaport sediments.

The dredged sediments of polluted seaports now raise complex management problems since it is no longer possible to discharge them into the sea. This results in the need to manage them on land, raising other types of technical, economic and environmental problems. Regarding the technical and economic dimensions, traditional waste treatment methods have proved to be poorly adapted, due to very high costs and low absorbable volumes.

Unicellular algae used as biosensors for chemical detection in Mediterranean lagoon and coastal waters.

Lagoons and coastal waters are contaminated by a large number of chemicals discharged directly or carried by rivers and runoff water that drain catchment areas in which agricultural activities take place. The inflow of these exogenous compounds constitutes a genuine risk for the health of ecosystems. It is therefore important to detect their presence in the natural environment before they cause irreversible damage.

Benefits and limits of sediment toxicity tests as an aid to decision-making.

With respect to the management of dredged sediments, a crucial issue is whether the removed materials (watered and/or processed) are disposed of or reused in an environmentally sound manner. In this context, the number of studies dealing with hazard or risk assessment has exponentially increased. This emphasis has resulted in the promotion and application of a very large variety of ecotoxicological tests.

Promoting effect of rapeseed proteins and peptides on Sf9 insect cell growth.

The Baculovirus Expression Vector System has become widely used for the production of recombinant proteins for research and diagnostics. Serum-free culture media able to support high cell densities have been developed for the large scale culture of insect cells. While serum elimination aims at avoiding the risks associated with the introduction of an ill defined component of bovine origin, additives such as protein hydrolysates from animal sources are still used.

Synchronous-scan fluorescence of algal cells for toxicity assessment of heavy metals and herbicides.

Synchronous-scan spectrofluorometry was applied to Chlorella vulgaris cells to assess the toxicity of heavy metals and herbicides in water. Simultaneous scan of both the excitation and emission spectra was done at a constant wavelength difference Deltalambda (20-140 nm) between the emission and excitation wavelengths in the range of 420-700 nm emission, where a peak of fluorescence was observed. Its position depends on Deltalambda.

Characterizing the risks to aquatic ecosystems: a tentative approach in the context of freshwater dredged material disposal.

The development of relevant frameworks for assessing ecological risks posed by dredged material management does not only involve an appropriate selection of assessment and measurement endpoints but also requires a sound approach to both risk characterization and the associated uncertainty. A formal methodology addressing both aspects has been developed in France for freshwater sediment deposits in water. Both exposure and effects measurements are 1st transformed into scores or classes.

Assessment of ecotoxicological risks related to depositing dredged materials from canals in northern France on soil.

The implementation of an ecological risk assessment framework is presented for dredged material deposits on soil close to a canal and groundwater, and tested with sediment samples from canals in northern France. This framework includes two steps: a simplified risk assessment based on contaminant concentrations and a detailed risk assessment based on toxicity bioassays and column leaching tests. The tested framework includes three related assumptions: (a) effects on plants (Lolium perenne L.

Assessment of the immunomodulatory activity of cheese extracts by a complete and easy to handle in vitro screening methodology.

A simple and rapid screening methodology based on the in vitro culture of murine hybridoma and human T-lymphocytes was developed to assess the potential immunomodulatory activity of water-soluble extracts (WSE) from cheese. The two immune cell lines were cultured in microplates with or without cheese WSE. The proliferation and the metabolic activity of cells were monitored at their different growth phases by the BrdU (5-bromo-2'-deoxyuridine) and MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenylterazolium bromide] assays, respectively.

A bi-enzymatic whole cell conductometric biosensor for heavy metal ions and pesticides detection in water samples.

A conductometric biosensor using immobilised Chlorella vulgaris microalgae as bioreceptors was used as a bi-enzymatic biosensor. Algae were immobilised inside bovine serum albumin membranes reticulated with glutaraldehyde vapours deposited on interdigitated conductometric electrodes. Local conductivity variations caused by algae alkaline phosphatase and acetylcholinesterase activities could be detected.

Development of novel conductometric biosensors based on immobilised whole cell Chlorella vulgaris microalgae.

A novel biosensor based on immobilised whole cell Chlorella vulgaris microalgae as a bioreceptor and interdigitated conductometric electrodes as a transducer has been developed and tested for alkaline phosphatase activity (APA) analysis. These sensors were also used for the detection of toxic compounds, namely cadmium ions, in aquatic habitats. Algae were immobilised inside bovine serum albumin (BSA) membranes cross-linked with glutaraldehyde vapours.

Optical whole-cell biosensor using Chlorella vulgaris designed for monitoring herbicides.

An optical biosensor was designed for determination of herbicides as aquatic contaminants. Detection was obtained with immobilised Chlorella vulgaris microalgae entrapped on a quartz microfibre filter and placed in a five-membrane-home-made-flow cell. The algal chlorophyll fluorescence modified by the presence of herbicides was collected at the tip of an optical fibre bundle and sent to a fluorimeter.

Positive role of peptidoglycan breaks in lactococcal biofilm formation.

Bacterial attachment to solid matrices depends on adhesive molecules present on the cell surface. Here we establish a positive correlation between peptidoglycan (PG) breaks, rather than particular molecules, and biofilm-forming capacity in the Gram-positive bacterium Lactococcus lactis. The L.

Optical algal biosensor using alkaline phosphatase for determination of heavy metals.

A biosensor is constructed to detect heavy metals from inhibition of alkaline phosphatase (AP) present on the external membrane of Chlorella vulgaris microalgae. The microalgal cells are immobilized on removable membranes placed in front of the tip of an optical fiber bundle inside a homemade microcell. C.