Évaluation de la contamination métallique dans deux lagunes marocaines: Khnifiss et Oualidia

L’objectif de la présente étude est d’évaluer la contamination métallique dans deux lagunes marocaines : Oualidia (située au centre du Maroc, dans une zone très urbanisée et industrialisée) et Khnifiss (située au sud du Royaume et loin de toute influence anthropique). Pour ce faire, les concentrations des métaux traces sont mesurées mensuellement durant un cycle annuel (décembre 2004 - janvier 2006) dans le sédiment des deux lagunes et chez Nereis diversicolor, annélide détritivore vivant dans le sédiment. La comparaison des teneurs métalliques dans le sédiment des deux écosystèmes lagunaires montre des niveaux relativement élevés en Ag, Cd et Zn dans la lagune de Oualidia. Ces teneurs sont probablement consécutives aux rejets urbains et industriels auxquels s’ajoutent ceux provenant des usines de transformation du minerai de phosphate (Safi et Jorf Lasfar situés respectivement au sud et au nord de ce site). Les teneurs des métaux analysées chez Nereis diversicolor montrent des variations saisonnières. Elles sont généralement élevées en hiver et au printemps ; ceci est probablement en relation avec le cycle de reproduction de l’animal. Concernant la comparaison des teneurs en métaux traces chez les annélides des deux lagunes, les concentrations chez les animaux à Khnifiss semblent plus élevées, suggérant une plus grande biodisponibilité de ces éléments dans cet écosystème peu contaminé

Argan [Argania spinosa (L.) Skeels] oil

Argan oil is extracted from the kernels of Argania spinosa (L.) Skeels, a tree that almost exclusively grows endemically in southern Morocco. If argan oil was initia11y only known around its traditional production area, major efforts combining chemical, agronomic and human sciences have led to its international recognition and marketing. In addition, to ensure the sustainable production of a sufficient quantity of argan kernels, a vast and unprecedented program that led to the reforestation of large areas of drylands has been developed in Morocco. Therefore, argan oil production is considered as an economic and ecologic success. Edible argan oil is prepared by cold-pressing roasted argan kernels. Unroasted kernels afford an oil of cosmetic grade, showing a bitter taste. Both oils, which are not refined and are virgin oils, share a similar fatty acid content that includes oleic and linoleic acids as major components. Additiona11y, argan oil is rich in antioxidants. Together, these components likely contribute to the oil pharmacological properties that, in humans, traditionally included cardiovascular disease and skin protection. Recent scientific studies have greatly expanded the scope of these pharmacological activities. Argan oil is now rewarded with a "Geographic Indication" that certifies its exclusive and authentic Moroccan origin and the compliance with strict production rules. In addition, the quality of argan oil can nowadays be ascertained by using an array of physicochemica1 methods. By-products, generated in large quantity during argan oil production, are also finding promising development routes

VEINCTR-N, an immunogenic epitope of Fas (CD95/Apo-I), and soluble Fas enhance T-cell apoptosis in vitro. II. Functional analysis and possible implications in HIV-1 disease.

BACKGROUND: Recent studies indicate that soluble Fas (sFas) may modulate T-cell apoptosis, since it inhibits Fas-ligand (Fas-L)-mediated cytotoxicity in vitro. Here, we explored whether the soluble receptor and its major immunogenic domain, namely VEINCTR-N, interfered with apoptosis of T cells from human immunodeficiency virus-type 1 (HIV-1)+ subjects showing serum elevations of both the soluble receptor and anti-Fas antibodies, and with that of several T-cell lines. MATERIALS AND METHODS: Both proliferation and apoptosis extent of T cells from 16 HIV-1+ patients showing serum anti-VEINCTR-N immunoglobulin G (IgG) and 15 controls were tested after incubation with sFas and three 8-mer peptides of its first consensus sequence that included VEINCTR-N. Several cell lines were also investigated by flow cytometry for their expression of Ki-67, the APO2.7-related mitochondrial protein, and the annexin-V. In addition, we evaluated the expression of Fas-L and caspases FLICE, CPP32 and ICE either by flow cytometry, immunoblotting, and/or reverse transcription polymerase chain reaction (RT-PCR). RESULTS: Cell proliferation in cultures from both patients and controls was affected significantly by sFas and VEINCTR-N. However, a prevalent increase of the subdiploid DNA-containing cell population occurred within these cultures. Similarly, Jurkat, CEM cells, and a mouse WR19L transformant overexpressing native human Fas underwent prompt apoptosis, which was detected as enlargement of APO2.7-reactive and annexin-V-positive populations. By exploring the Fas pathway in Jurkat cells, we found that both apoptosis inducers acted through Fas, since Fas-L, as well as CPP32 and FLICE were activated. By contrast, ICE was up-regulated only in control cells treated with tumor necrosis factor alpha (TNFalpha). CONCLUSIONS: These data suggest that the soluble molecular forms of Fas prime cell death in Fas-positive cells. Therefore, the shedding of high amounts of sFas in HIV- 1 disease is possibly entrusted with amplification of the death execution program by cells functionally exhausted and committed to die. It is conceivable that the appearance of anti-Fas antibodies reflects an attempt by the immune system to neutralize these effective forms of the receptor and its structurally degraded domains, such as VEINCTR-N