Correlation between free and total vancomycin serum concentrations in patients treated for Gram-positive infections.

Routine therapeutic drug monitoring (TDM) reports only total vancomycin (VAN) concentrations, although protein binding varies and it is generally accepted that only free VAN is active. The aims of this study were to examine the correlation between free and total VAN concentrations in order to estimate whether free VAN levels can be predicted based on its total concentration. A high-performance liquid chromatography (HPLC) method was set up and validated (against routine laboratory immunoassays) for measurement of free [ultrafiltration (Centrifree); cut-off 30 kDa] and total [solid-phase extraction (Oasis MCX cartridge)] VAN in serum.

Design and evaluation of analogues of the bacterial cell-wall peptidoglycan motif L-Lys-D-Ala-D-Ala for use in a vancomycin biosensor.

Four small molecular receptors of vancomycin have been designed to make part of a novel biosensor device based on the FTIR-ATR detection: N-Boc (2a) or N-Ac (2b)-6-aminocaproyl-D-Ala-D-Ala and N-Boc (3a) or N-Ac (3b)-6-aminocaproyl-D-Ala-d-Ser. Using an original microbiological approach to assess the competition of compounds with the natural target of vancomycin in bacteria, EC(50) values of 6.3-8.

Serum pneumoproteins and biomarkers of exposure to urban air pollution: a cross-sectional comparison of policemen and foresters.

Very few biomarkers are available for the non-invasive detection of effects of urban air pollution on the respiratory tract. The objective was to evaluate whether Clara cell protein (CC16) and surfactant-associated protein-A (SP-A), two pulmonary secretory proteins, were useful in the detection of effects of urban air pollutants on the pulmonary epithelium. These proteins were determined in the serum of 53 policemen working in Brussels, Belgium, and a control group of 59 foresters working in the countryside.

Simultaneous determination of the antiretroviral agents: amprenavir, lopinavir, ritonavir, saquinavir and efavirenz in human peripheral blood mononuclear cells by high-performance liquid chromatography-mass spectrometry.

A selective and accurate assay for the simultaneous quantitation of four protease inhibitors (PIs) (amprenavir (APV), lopinavir (LPV), ritonavir (RTV) and saquinavir (SQV)) and a non-nucleoside reverse transcriptase inhibitor (NNRTI) (efavirenz, EFV) in human peripheral blood mononuclear cells using high-performance liquid chromatography-mass chromatography (LC/MS) has been developed and validated. After liquid-liquid extraction, the antiretroviral agents were separated within 15 min. The calibration curves of each drug showed a good linearity in a range of concentration between 2 and 200 ng/3 x 10(6) cells for amprenavir, lopinavir, efavirenz, 1.

Virological, intracellular and plasma pharmacological parameters predicting response to lopinavir/ritonavir (KALEPHAR study).

Objectives: To assess the impact of HIV-1 protease mutations and intracellular and plasma lopinavir minimum concentrations (Cmin) on virological success or failure on lopinavir/ritonavir-containing highly active antiretroviral therapy (HAART).

Design: HIV-1-infected HAART-experienced patients included in an observational study, received lopinavir/ritonavir (400/100 mg twice a day) plus two to three nucleoside reverse transcriptase inhibitors (NRTI) or one NRTI plus one non-NRTI. A viral load less than 50 copies/ml at month 6 defined virological success.