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1.
Sci Total Environ ; 954: 176624, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39362564

ABSTRACT

Despite their intensive use and their impact on ecosystems, biocides and surfactants are still poorly regulated and poorly monitored at large scale. In the frame of the revision of the national regulatory surveillance plan of surface waters, France planned in 2018 a monitoring campaign at national scale focused on these two types of substances of very emerging concern. Forty-nine contaminants (32 biocides and 17 surfactants) were investigated in surface water and sediment samples from 91 sampling sites, and in effluent and sludge samples of 7 wastewater treatment plants (WWTP), in mainland France and overseas regions. Between 33 and 52 % of the target contaminants were quantified at least once in water and sediment. High frequencies of quantification were observed for the surfactants (up to 91 % in water samples and up to 57 % in sediment samples for LAS C10-C13) and for the biocides (up to 64 % for fipronil in water samples and up to 90 % for methyl nonyl ketone in sediment samples). The median concentrations of surfactants were up to 2 µg/L in mainland surface water samples and up to 528 µg/kg in sediment samples, and for biocides, the median concentrations were up to 0.18 µg/L in mainland surface water samples and up to 104 µg/kg in sediment samples. PNEC exceedances in water and sediment were determined for both types of substances. The analysis of effluent and sludge suggested significant but not total removal of these substances in the WWTP. Temporal and spatial variations of the concentrations of both types of substances in surface water samples were also observed, suggesting both punctual and diffuse contamination sources of the surface water investigated.

2.
Environ Sci Pollut Res Int ; 22(3): 2106-16, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25167822

ABSTRACT

Siderophores are chelators with a high selectivity for Fe(III) and a good affinity for divalent metals, including Cd(II) and Ni(II). Inoculation with siderophore-producing bacteria (SPB) has thus been proposed as an alternative to chelator supply in phytoremediation. Accurate assessments of the potential of this association require a dissection of the interaction of siderophores with metals at the soil-root interface. This study focuses on pyoverdine (Pvd), the main siderophore produced by Pseudomonas aeruginosa. We first assessed the ability of Pvd to coordinate Ni(II). The stability constant of Pvd-Ni(II) (log K (L'Ni) = 10.9) was found to be higher than that of Pvd-Cd(II) (log K (L'Cd) = 8.2). We then investigated the effect of a direct supply of Pvd on the mobilization, speciation, and phytoavailability of Cd and Ni in hydroponics. When supplied at a concentration of 50 µM, Pvd selectively promoted Ni mobilization from smectite. It decreased plant Ni and Cd contents and the free ionic fractions of these two metals, consistent with the free ion activity model. Pvd had a more pronounced effect for Ni than for Cd, as predicted from its coordination properties. Inoculation with P. aeruginosa had a similar effect on Ni phytoavailability to the direct supply of Pvd.


Subject(s)
Cadmium/metabolism , Environmental Pollutants/metabolism , Hydroponics , Nickel/metabolism , Oligopeptides/pharmacology , Solanum lycopersicum/drug effects , Solanum lycopersicum/metabolism , Biodegradation, Environmental , Cadmium/chemistry , Cadmium/isolation & purification , Environmental Pollutants/chemistry , Environmental Pollutants/isolation & purification , Solanum lycopersicum/growth & development , Solanum lycopersicum/microbiology , Nickel/chemistry , Nickel/isolation & purification , Oligopeptides/biosynthesis , Plant Roots/metabolism , Pseudomonas aeruginosa/metabolism , Siderophores/biosynthesis , Siderophores/pharmacology , Silicates/chemistry , Soil/chemistry
3.
Chemosphere ; 103: 212-9, 2014 May.
Article in English | MEDLINE | ID: mdl-24359916

ABSTRACT

Enhanced metal phytoextraction by the use of siderophore-producing bacteria (SPB) has received a lot of attention in the past decade. Bacterial siderophores are able to bind a wide range of metals other than iron and thus should enhance their phytoavailability in contaminated matrices. However, the impact of bacterial siderophores in the soil-plant transfer of metals is not yet fully elucidated, as underlined by the opposing results reported in the literature regarding the efficiency of coupling phytoextraction with bioaugmentation by SPB. The present study focuses on one bacterial siderophore, the pyoverdine (Pvd), produced by Pseudomonas aeruginosa. The coordination properties of Pvd towards Cd(II) and Cu(II) were determined and the effect of Pvd supply was assessed on (i) the mobility (CaCl2 extractions), (ii) the phytoavailability (DGT measurements) and (iii) the phytoextraction of Cd and Cu, in a calcareous soil. The stability constant of Pvd-Cu (KL'Cu=10(20.1)) was found much higher than that of Pvd-Cd (KL'Cd=10(8.2)). The major finding was the agreement observed between Pvd coordination properties and Pvd impact on metals phytoextraction. Pyoverdine, supplied at 250 µmol kg(-1) soil, enhanced the mobility, the phytoavailability and the phytoextraction of Cu while the fate of Cd was not affected. All these results were compared to those reported for chelate-assisted phytoextraction. Their relevance in using SPB for phytoremediation is discussed.


Subject(s)
Cadmium/metabolism , Copper/metabolism , Oligopeptides/chemistry , Pseudomonas aeruginosa/metabolism , Siderophores/chemistry , Soil Pollutants/metabolism , Biodegradation, Environmental , Oligopeptides/metabolism , Siderophores/metabolism
4.
Med Trop (Mars) ; 60(4): 357-60, 2000.
Article in French | MEDLINE | ID: mdl-11436588

ABSTRACT

Hepatitis due to Listeria monocytogenes is uncommon in adults. This report describes the first case observed in Senegal. The patient was a 73-year old man presenting listeria-related hepatitis presumably secondary to low-grade meningeal encephalitis. Treatment using ampicillin was unsuccessful and the patient died four days after hospitalization. The authors note that the incidence of adult listeriosis has risen constantly for the past twenty years in relation with alcohol abuse, cirrhosis, diabetes, kidney insufficiency, cancer, AIDS, and organ transplantation. However no predisposing factors were observed in the present case.


Subject(s)
Hepatitis/microbiology , Meningitis, Listeria/complications , Aged , Ampicillin/therapeutic use , Fatal Outcome , Hepatitis/diagnosis , Humans , Male , Meningitis, Listeria/diagnosis , Meningitis, Listeria/drug therapy , Meningitis, Listeria/epidemiology , Penicillins/therapeutic use , Risk Factors , Senegal/epidemiology
5.
Toxicol Lett ; 18(1-2): 153-6, 1983 Aug.
Article in English | MEDLINE | ID: mdl-6623540

ABSTRACT

The effects of vitamin C on acute paracetamol poisoning were studied in mice. Given orally at 50, 100 or 200 mg/kg, either simultaneously or 2 h after the oral administration of 875 mg/kg of paracetamol, vitamin C did not cause any decrease in the mortality rate. In similar conditions in previous experiments methionine and cysteine were shown to be very effective antidotes.


Subject(s)
Acetaminophen/poisoning , Ascorbic Acid/pharmacology , Acute Disease , Animals , Female , Male , Mice , Mice, Inbred Strains
6.
Eur J Gynaecol Oncol ; 2(2): 43-7, 1981.
Article in English | MEDLINE | ID: mdl-7338257

ABSTRACT

The Authors report two cases of cancer of the uterine cervix in which the clinical debut was by extrapelvic metastases and in which the local gynecological exploration placed the patient in a clinical stage Ib.


Subject(s)
Carcinoma, Squamous Cell/pathology , Uterine Cervical Neoplasms/pathology , Adult , Biopsy , Bone Neoplasms/secondary , Cervix Uteri/pathology , Female , Humans , Liver Neoplasms/secondary , Lung Neoplasms/secondary , Middle Aged
7.
Z Tierpsychol ; 41(2): 121-41, 1976 Jun.
Article in German | MEDLINE | ID: mdl-961123

ABSTRACT

The Mediterranean blenny Blennius rouxi has been studied mainly in the Banyuls-sur-Mer region. Data on its behaviour have been obtained by skin diving, SCUBA diving and observations in captivity. At Banyuls-sur-Mer Blennius rouxi lives at a depth of 1 to 42m. As an exception among Mediterranean blennies, Bl. rouxi feeds by grazing off the substrate. Algae, sponges and polychaetes (Sedentaria) are the main components of its food (HEYMER and ZANDER, in press). We could not confirm that the colouration, a white body with a conspicuous dark horizontal band, can be regarded as a signal of cleaning activity in statu nascendi. The male male have a spatial territory in which they occupy haptic holes. The female female lead a vagabond life and actively join the male male in their territories during the breeding season. Head nodding is an agonistic behaviour against other female female and has an attractive significance for spawning-motivated female female. The male male threaten with a widely opened mouth (threat yawning). Our data and observations on the ethology of Bl. rouxi are discussed and compared with those known of Bl. sphinx, Bl. incognitus, and Bl. zvonimiri, its nearest relatives.


Subject(s)
Behavior, Animal , Fishes , Agonistic Behavior , Animals , Feeding Behavior , Female , Male , Sexual Behavior, Animal
8.
Bull Cancer ; 63(1): 73-86, 1976.
Article in French | MEDLINE | ID: mdl-825163

ABSTRACT

Pigmented melanomas were induced in the Syrian golden hamster by oral administration of 9, 10-dimethyl 1,2-benzanthracene. The primary tumors were grafted into new animals to obtain a series of transplantable tumors. The grafted tumors show the malignant characters which are not present in the primary tumors. These were studied clinically, histologically and ultrastructurally. We believe that this transformation occured perhaps as a consequence of the selection of cells which have a more prominent tendency toward malignancy. This selection could be explained by a greater resistance of lesser pigmented melanocytes or by their weak immunologic capacity. The malignant potential of these cells could eventually be correlated with the presence of viral particles which act as cocarcinogens.


Subject(s)
9,10-Dimethyl-1,2-benzanthracene , Benz(a)Anthracenes , Melanoma/pathology , Animals , Cricetinae , Male , Melanocytes/ultrastructure , Melanoma/chemically induced , Melanoma/ultrastructure , Mesocricetus , Neoplasm Transplantation , Transplantation, Homologous
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