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Twenty-four children, ten of whom had an infection due to ticarcillin-resistant, Timentin-sensitive bacteria, were treated with Timentin. A full clinical success was obtained in sixteen cases (13 pyelonephritis, nine of them due to ticarcillin-resistant, Timentin-sensitive Escherichia coli, two neonatal infections and one pneumonia). Four children were improved (1 bronchiectasis, 3 leukaemias), three were unassessable and one failure occurred with a staphylococcal urinary tract infection. A pharmacokinetic study was performed in three newborns (under three months) and ten children (mean age 3 years). Timentin was administered as four daily 30-min iv infusions. The mean dosage used in patients under three months was 225 mg/kg/d ticarcillin and 9 mg/kg/d clavulanic acid. In infants older than three months of age the mean dosage was 250 mg/kg/d ticarcillin and 16 mg/kg/d clavulanic acid. The pharmacokinetic results demonstrated similar serum concentrations of ticarcillin to those in earlier studies, and serum concentrations of clavulanic acid of 3.1±0.63 mg/1 and 2.18±0.17 mg/1 at 1 h and 2 h respectively after infusion in newborns. For children, at the same times, the serum levels were respectively 2.3±0.9 mg/1 and 1.4±0.9 mg/1. The peak serum concentrations of clavulanic acid were the same in the two groups of dosages (4.7 mg/1), but the half-lives of clavulanic acid were 1.1 h in children older than three months and 1.8 h in infants younger than 3 months. The tolerance was good.Timentin may be useful as a first line antibiotic in infections in hospitalized children in the dosage described, as three or four injections daily, according to the age and the severity of the disease. [ABSTRACT FROM PUBLISHER]

The deficiencies observed in the larval development of several populations of the sea urchin Sphaerechinus granularis from the Bay of Brest were used to evaluate the quality of seawater. The comparison of ecotoxicological indices reveal that there are significant differencesbetween the reference populations and the populations located in thecentre and northern areas of the Bay, the sea urchins living at the mouth of the river Aulne having the highest level of blockage and delay in embryonic development. Analysis of heavy metals present within the sea urchin gonads reveals concentrations that are 2-5 times higher than those observed in the other populations of the Bay. A discussion is carried out based on these results and on different environmental factors. The developmental abnormalities observed at this site could be linked to dumping of heavy metals from pyrotechnical waste but also to dumping of pesticides from agricultural sources, and TBT plusPAHs concentrations from urban and port activities. [ABSTRACT FROM AUTHOR]

The herbicide bentazon (CASRN 25057-89-0) is extensively used in agriculture in Brittany (France) to replace atrazine. Bentazon is not readily adsorbed by soil and therefore it enters adjacent freshwater ecosystems, making its way to estuarine and marine waters areas. Information regarding its effects on marine ecosystems is scarce. Phytotoxicity assessments were conducted in the laboratory on the common diatom Chaetoceros gracilis using both the active ingredient and its formulated product (Basamaïs). The 3 day EC(50) using cell counts were, respectively, 150 mg/L and 60 microg/L for bentazon active ingredient and for bentazon-formulated while cellular volume was increased. Although bentazon is known as a photosystem II inhibitor, it produced an increase of pigment (chlorophylls a, c, and carotenoids) content, ATP synthesis, rates of photosynthesis and respiration, and TBARS formation. Therefore, pigments cannot be used as biomarkers of toxicity. Algal cell recovery from bentazon effects occurred after 6-9 days, suggesting a tolerance mechanism.

Effects of the herbicide Basamaïs (bentazon) and the fungicide Opus (epoxiconazole) on oyster spat (Crassostrea gigas) were assessed using in-situ microcosms in a field experiment lasting 13 days. Six-week-old hatchery spat (mean size 1.1 mm), previously collected on PVC plates, was immersed in glass bottles filled with 200 mum filtered seawater. Bottles were maintained underwater at 6 m depth and their water content changed every other day. Growth, measured as shell area index increase, was 126 +/- 4% in the control bottles. While no growth differences were observed between control and individual pesticide treatments at 10 microg l(-1), oysters treated with a mix of 10 microg l(-1) Opus and 10 microg l(-1) Basamaïs showed a 50% growth reduction compared with the control (P < 0.0001), suggesting a synergistic effect of these contaminants. Laboratory controls in microcosms maintained in a water bath with filtered natural light, were not significantly different from in-situ microcosm controls in the field, for organic weight content or growth. This in-situ experiment in microcosms allowed us to conclude that: (1) oyster spat can achieve significant growth in bottles immersed in situ without supplementary food; (2) this microcosm system is reliable and easy to use for environmental toxicity tests with C. gigas spat; (3) such microcosm systems can also be run in a laboratory water bath instead of more technically difficult immersed field experiments; (4) the synergistic effect observed here, at a concentration simulating a peak agricultural runoff event, suggests that the impacts of pesticides could be a real threat for oysters in estuarine areas.

Extraction followed by reverse phase liquid chromatography (LC)/electrospray ionization-ion trap-mass spectrometry (ESI-IT-MS) analysis has been successfully developed for the determination of peptaibols, fungal toxic metabolites, in marine sediments. Spiking experiments showed that the mean recovery of target compounds exceeded 85% at a spiking level of 10 ng/g of sediment (wet weight). Detection and quantification limits were 250 and 830 pg/g of sediment, respectively. The method developed constituted the first sensitive assay for quantification of peptaibol trace amounts in a natural environment. A concentration of 5 ng/g in sediment samples collected from Fier d'Ars was found.

Peptaibols are known membrane-modifying peptides that were recently detected in marine sediments and mussels collected from a shellfish farming area (Fier d'Ars, Atlantic coast, France). In this investigation, embryotoxicity bioassays with oysters (Crassostrea gigas) were performed to assess acute toxicity of alamethicin and different groups of peptaibols produced by a Trichoderma longibrachiatum strain isolated from marine environment. C. gigas embryos appeared very sensitive to all the metabolites examined with higher toxic effects for long-sequence peptides (EC50 ranging from 10 to 64 nM). D-shaped larvae with mantle abnormality were particularly noticed when peptaibol concentrations increased. Disturbances of embryogenesis were also observed following exposure to organic and aqueous extract of sediments from Fier d'Ars (EC50=42.4 and 6.6 g L(-1) dry weight, respectively). Although peptaibol concentrations measured in these sediments could explain only a part of the toxic effects observed, this study suggests that these mycotoxins can induce larval abnormalities in a population of exposed animals at environmentally realistic concentrations. Their detection in coastal areas devoted to bivalve culture should be taken into account.

Larval stages of bivalve molluscs are highly sensitive to pollutants. Oysters from a hatchery from Normandy (English Channel) were induced to spawn, and fertilized eggs were exposed to copper or cadmium for 24 h. Metal accumulation (from 0.125 to 5 microg Cu L(-1) and from 25 to 200 microg Cd L(-1)) and MT concentrations were measured in larvae. Compared to controls, larvae accumulated copper and cadmium with an increase in MT concentrations particularly with cadmium (i.e. 130.96 ng Cu (mg protein)(-1) and 12.69 microg MT (mg protein)(-1) at 1 microg Cu L(-1) versus 23.19 ng Cu (mg protein)(-1) and 8.92 microg MT (mg protein)(-1) in control larvae; 334.3 ng Cd (mg protein)(-1) and 11.70 microg MT (mg protein)(-1) at 200 microg Cd L(-1) versus 0.87 ng Cd (mg protein)(-1) and 4.60 microg MT (mg protein)(-1) in control larvae). Larvae were also obtained from oysters of a clean area (Arcachon Bay) and a polluted zone (Bidassoa estuary) and exposed to copper in the laboratory, their MT concentration was measured as well as biomarkers of oxidative stress. Biomarker responses and sensitivity to copper for the larvae from Arcachon oysters were higher than for those from Bidassoa.

This study aims to assess the effects of two pesticides, namely the insecticide carbofuran and the herbicide isoproturon, on monospecifically cultivated marine and freshwater phytoplankton according to standard methods. In the presence of pesticide, growth rates were lower in marine species Chaetoceros gracilis and Phaeodactylum tricornutum than in freshwater species Chlorella vulgaris and Selenastrum capricornutum after 72 hours. The EC50 values were obtained with the REGTOX Macro software, and the NEC values by applying the DEBtox model.

Ethylene glycol monomethyl ether (EGME) and ethylene glycol monomethyl ether acetate (EGMEA) have been tested for their acute and chronic toxicity to various organisms occupying different trophic levels in the aquatic ecosystems. The results obtained in this study and those collected from the literature clearly reveal that EGME does not present short- or long-term ecotoxic effects in the ranges of concentrations likely to be found in aquatic environments. Indeed, in general, concentrations of 1000 to 10,000 mg/L of EGME are necessary before significant adverse effects can be observed in aquatic species. Conversely, acute toxicity occurs in fish at about 50 mg/L of EGMEA, and reproduction of Ceriodaphnia dubia is affected by 0.06 mg/L of this chemical. A teratogenic effect-with a specific malformation of the eyes-occurs in Xenopus laevis in the presence of 75 mg/L of EGMEA. This study was partially supported by the French Ministry of the Environment as part of the PNETOX program (1998).

Serum antibodies were measured repeatedly in 176 cases of urinary tract infections in children. The method used, passive haemagglutination with the bacterial antigen of the patient's urinary infection, gives a positive reading from 1/160. Antibodies were found in 139 cases and the lower limit compatible with a diagnosis of pyelonephritis was 1/2560. The result may, however, be negative in infants of less than one year. As in the first publication, the authors describe three types of curves of progression. Analysis confirms the relationship between persistent antibodies and evolutive pyelonephritis. Experimental results and a comparison of clinical and pathological findings are discussed and support the notion of the value of a persistent high antibody level in the diagnosis of chronic pyelonephritis.

Tonsillar diffusion of two antibiotics was compared in 61 children, 26 receiving 100 mg/kg/d of ampicillin, and the other 35 being treated with 50 mg/kg/d of triacetyloleandomycin during the 24 hours preceding tonsillectomy. Drug levels were measured by a microbiological method. The mean ampicillin level in the tonsil was 0,84 mcg/ml for a serum level of 4,1 mcg/ml 90 minutes before sampling, concentrations being absent in the tonsil in 12 cases (45 p. cent). Mean triacetyloleandomycin levels in the tonsil were 12,16 mcg/ml for a serum level of 2,27 mcg/ml 90 minutes before sampling, concentrations being absent in the tonsil in only 4 cases (11 p. cent). Very high concentrations of triacetyloleandomycin as against low or no levels of ampicillin were therefore detected in the tonsil. This suggest that macrolides should be employed in preference to ampicillin for the treatment of recurrent sore throats, and tonsillixis, and for preventive treatment of acute rheumatic fever.

A study of the pharmacokinetics of cefoperazone (CPZ), used as the sole antibiotic, was performed in 17 children and neonates. The types of infections treated were 7 UTI, 2 otitis media, 2 RTI, 4 septicemia or severe neonatal infections. Causative bacteria included 6 E. coli, 3 Pseudomonas aeruginosa, 1 C perfringens, 1 Klebsiella pneumoniae and 2 Staphylococcus aureus. Cefoperazone was administered by means of rapid IV injections (over 5 min) or IV infusions BID. The blood samples were taken by means of capillary microtubes at time 0, 0.25, 0.50, 0.75, 1, 2, 4, 6, 8 and 12 hours after the end of the first injection. After centrifugation and freezing at -80 degrees DEG method using modified Difco M2 Agar (Nall plus sodium citrate) and stock organinism Bacillus subtilis Atcc 6633. The results achieved in children and neonates were compared, in the 11 children (mean age 6.5 years). The mean single dose was 53 mg/kg. The mean maxima concentration was 145 mcg/ml and was obtained at 0.5 h. Mean serum half-life is 2.4 h. For the neonates mean age was 16 days and the dosage was 47 mg/kg, the maxima concentration was 232 micrograms/ml and was obtained at 0.6 h. The mean serum half-life was 3.4 h in the 2 groups, serum levels at 12 h were still high with a mean of 6.2 micrograms/ml for the 17 children. It appears that doses of 25-50 mg/kg given BID would be satisfactory.