DECREASE OF 5-HYDROXYINDOLEACETIC ACID (5-HIAA) EXCRETION IN OLD AGE.

This review provides an overview of the on-line coupling of solid-phase extraction or liquid chromatography with gas chromatography for the analysis of biological samples. Principles relevant to techniques are briefly presented and selected applications are described. Benefits of the coupled systems are discussed.

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PubMed2005

Bioanalysis of drugs by liquid-phase microextraction coupled to separation techniques.

The demand for automation of liquid-liquid extraction (LLE) in drug analysis combined with the demand for reduced sample preparation time has led to the recent development of liquid-phase microextraction (LPME) based on disposable hollow fibres. In LPME, target drugs are extracted from aqueous biological samples, through a thin layer of organic solvent immobilised within the pores of the wall of a porous hollow fibre, and into an microl volume of acceptor solution inside the lumen of the hollow fibre. After extraction, the acceptor solution is subjected directly to a final analysis either by high performance liquid chromatography (HPLC), capillary electrophoresis (CE), mass spectrometry (MS), or capillary gas chromatography (GC) without any further treatments. Hollow fibre-based LPME may provide high enrichment of drugs and excellent sample clean-up, and probably has a broad application potential within the area of drug analysis. This review focuses on the principle of LPME, and recent applications of three-phase, two-phase, and carrier mediated LPME of drugs from plasma, whole blood, urine, and breast milk.

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PubMed2005

HFOV in premature neonates: effects on pulmonary mechanics and epithelial lining fluid cytokines. A randomized controlled trial.

OBJECTIVE: Ventilation strategies for preterm neonates may influence the severity of pulmonary dysfunction and later development of chronic lung disease. The objective of this report is to compare the effects of high-frequency oscillatory ventilation (HFOV) versus synchronized intermittent mandatory ventilation (sIMV) from the points of views of biochemical and functional variables. DESIGN: Randomized controlled trial. SETTING: Third level NICU. PATIENTS AND PARTICIPANTS: Forty preterm neonates with a gestational age of 24-29 weeks were randomly assigned to one of the two above-mentioned ventilation strategies within 30 min from birth. MEASUREMENTS AND RESULTS: At 1, 3, 5, and 7 days, the babies were monitored by means of ventilator indices, pulmonary function, and eight pro-inflammatory or anti-inflammatory cytokines measured in bronchoalveolar lavage fluid. The neonates assigned to the HFOV procedure benefited from early and sustained improvement in pulmonary mechanics and gas exchange-significantly higher dynamic respiratory compliance values, significantly lower expiratory airway resistance and oxygenation index values-with earlier extubation as compared to the neonates assigned to sIMV treatment, and showed significantly lower transforming growth factor-beta1 concentrations in bronchoalveolar lavage fluid. CONCLUSIONS: The results of this randomized clinical trial support the hypothesis that early and exclusive use of HFOV, combined with optimum volume strategy, has a beneficial effect during the acute phase of lung injury.

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