Éditeur(s) : HAL CCSD American Society for Microbiology
Résumé : International audience
A rapid and specific high-performance liquid chromatography method with UV detection (HPLC-UV) for the simultaneous determination of 12 beta-lactam antibiotics (amoxicillin, cefepime, cefotaxime, ceftazidime, ceftriaxone, cloxacillin, imipenem, meropenem, oxacillin, penicillin G, piperacillin, and ticarcillin) in small samples of human plasma is described. Extraction consisted of protein precipitation by acetonitrile. An Atlantis T3 analytical column with a linear gradient of acetonitrile and a pH 2 phosphoric acid solution was used for separation. Wavelength photodiode array detection was set either at 210 nm, 230 nm, or 298 nm according to the compound. This method is accurate and reproducible (coefficient of variation [CV] < 8%), allowing quantification of beta-lactam plasma levels from 5 to 250 μg/ml without interference with other common drugs. This technique is easy to use in routine therapeutic drug monitoring of beta-lactam antibiotics.
ISSN: 0066-4804

hal-00875271
https://hal.archives-ouvertes.fr/hal-00875271
https://hal.archives-ouvertes.fr/hal-00875271/document
https://hal.archives-ouvertes.fr/hal-00875271/file/Simultaneous_Determination-accepted.pdf
PUBMED : 21788467

Éditeur(s) : HAL CCSD American Mosquito Control Association
Résumé : Research on natural insecticides has intensified with the spread of resistance to chemicals among insects, particularly disease vectors. To evaluate compounds, the World Health Organization (WHO) has published standardized procedures. However, those may be excessively compound-consuming when it comes to assessing the activity of natural extracts and pure compounds isolated in limited amount. As part of our work on the discovery of new mosquito larvicides from Amazonian plants, we developed a compound-saving assay in 5-ml glass tubes instead of WHO larval 100-m1 cups. Comparing activity of synthetic and natural chemicals validated the glass tube assay. Raw data, lethal doses that kill 50% (LD50) and 90% (LD90) at 24 and 48 h, were highly correlated (0.68 < R-2 < 0.96, P < 0.001, Pearson test) between cups and tubes. It was also established that 10 tubes (N = 50 larvae) provided the same level of sensitivity as 20 tubes (N= 100). This method proved suitable for rapid screening of natural extracts and molecules, identifying active compounds using 10 times less material than in the WHO protocol.
ISSN: 8756-971X

hal-01602207
https://hal.archives-ouvertes.fr/hal-01602207
DOI : 10.2987/16-6613.1
PRODINRA : 394297
PUBMED : 28206865

Éditeur(s) : HAL CCSD
Résumé : International audience
o abstract
11e Congrès Français de Sédimentologie,
Unknown, Unknown or Invalid Region

hal-01426592
https://hal.archives-ouvertes.fr/hal-01426592

Éditeur(s) : HAL CCSD Société géologique de France
Résumé : The Maguelone shore extends along the northern coast of the Gulf of Lions margin, West of the Rhone delta and East of some high gradient coastal streams that have been providing most of the elastic sediments to the Gulf of Lions margin since the early Miocene. This 10 km wide area comprises an onshore small coastal watershed (15 km long) in low-lying carbonate hills, kilometer wide marshes, sandy beach and shoreface featuring local low sedimentation. Deposit architecture in such a coastal zone records dynamics of incised valley fill under the influence of rivers and wave/current hydrodynamics in a microtidal environment during an eustatic cycle.;A detailed analysis of about 250 km of very high resolution seismic profiles, tens of cores and outcrops data revealed the evolution of the Maguelone coastal system from Late-Quaternary to present-day. It highlighted also dominant denudation processes in the upstream catchments associated to the formation of incised valley seaward during Quaternary. Combination of this inherited morphology together with hydrodynamics controlled the lagoonal environment evolution since the last transgression. In particular, the Maguelone shore is characterized by the formation of built-over-rias lagoonal systems and records an evolution from partially protected lagoon to isolated lagoon environment. These two stages of lagoon evolution correspond to distinct deposit environments. Correlation of fauna contents with deposit geometry improves lagoonal environment models.
EISSN: 1777-5817

hal-00486370
https://hal.archives-ouvertes.fr/hal-00486370
DOI : 10.2113/gssgfbull.181.2.211

Éditeur(s) : HAL CCSD Maney Publishing
Résumé : International audience
The aim of the present retrospective observational clinical study was to assess the interindividual pharmacokinetic variability of plasma concentrations of amoxicillin or cloxacillin administered in high doses intravenously in critically ill patients, related to renal function or administration method.Four hundred and two plasma concentrations were measured at steady-state with a high performance liquid chromatography technique in 162 patients treated with 100 - 300 mg/kg/day of intravenous amoxicillin or cloxacillin.For both drugs and administration methods, plasma concentrations were significantly higher for patients with creatinine clearance below 60 ml/min, even though doses were adapted for renal impairment. the correlations calculated between plasma concentrations and creatinine level, creatinine clearance or doses were all low. There were fewer outlying drug concentrations in patients receiving continuous rather than intermittent regimens.Our results are in favor of adapting dosages of these beta-lactam antibiotics based on plasma concentrations, especially in cases of renal impairment.
ISSN: 1120-009X

hal-00875258
https://hal.archives-ouvertes.fr/hal-00875258
DOI : 10.1179/joc.2011.23.5.277
PUBMED : 22005059