Bacterial-type oxygen detoxification and iron-sulfur cluster assembly in amoebal relict mitochondria.

The assembly of vital reactive iron-sulfur (Fe-S) cofactors in eukaryotes is mediated by proteins inherited from the original mitochondrial endosymbiont. Uniquely among eukaryotes, however, Entamoeba and Mastigamoeba lack such mitochondrial-type Fe-S cluster assembly proteins and possess instead an analogous bacterial-type system acquired by lateral gene transfer. Here we demonstrate, using immunomicroscopy and biochemical methods, that beyond their predicted cytosolic distribution the bacterial-type Fe-S cluster assembly proteins NifS and NifU have been recruited to function within the relict mitochondrial organelles (mitosomes) of Entamoeba histolytica.

Confirmatory analysis for drugs of abuse in plasma and urine by high-performance liquid chromatography-tandem mass spectrometry with respect to criteria for compound identification.

Recently, high-performance liquid chromatography-tandem mass spectrometry (LC/MS/MS) has become a powerful tool for quantitative confirmatory analysis of drugs of abuse and has begun to spread in the field of forensic toxicology. Guidelines for confirmatory analysis by GC/MS and LC/MS/MS have been published recently by several organizations (WADA, IOC, SOFT, GTFCh, EU). However, these guidelines have not yet been included in procedures for drug analysis with LC/MS/MS.

Simultaneous determination of Delta9-tetrahydrocannabinol, 11-hydroxy-Delta9-tetrahydrocannabinol and 11-nor-9-carboxy- Delta9-tetrahydrocannabinol in human plasma by high-performance liquid chromatography/tandem mass spectrometry.

A rapid and sensitive method for the simultaneous confirmatory analysis of three forensic most relevant cannabinoids, Delta(9)-tetrahydrocannabinol (THC), 11-hydroxy-Delta(9)-tetrahydrocannabinol (11-OH-THC) and 11-nor-9-carboxy-Delta(9)-tetrahydrocannabinol (THC-COOH), by means of high-performance liquid chromatography/tandem mass spectrometry (LC/MS/MS) in human plasma was developed and fully validated. Sample clean-up was performed by automated silica-based solid-phase extraction and the separation was carried out using a PhenylHexyl column (50 x 2 mm i.d.

Supercritical fluid extraction of steroids from biological samples and first experience with solid-phase microextraction-liquid chromatography.

Modern extraction techniques, supercritical fluid extraction (SFE) and solid-phase microextraction (SPME) were used for isolation of four corticosteroids from biological matrices. SFE was applied for extraction from solid matrices--hydromatrix and pig muscle. The effects of various extraction conditions were studied.