Solid phase microextraction and LC-MS/MS for the determination of paliperidone after stereoselective fungal biotransformation of risperidone

The present work describes for the first time the use of SPME coupled to LC-MS/MS employing the polar organic mode in a stereoselective fungal biotransformation study to investigate the fungi ability to biotransform the drug risperidone into its chiral and active metabolite 9-hydroxyrisperidone (9-RispOH). The chromatographic separation was performed on a Chiralcel OJ-H column using methanol:ethanol (50:50, v/v) plus 0.2% triethylamine as the mobile phase at a flow rate of 0.8 mL min(-1). The SPME process was performed using a C18 fiber, 30 min of extraction time and 5 min of desorption time in the mobile phase. The method was completely validated and all parameters were in agreement with the literature recommendations. The Cunninghamella echinulata fungus was able to biotransform risperidone into the active metabolite, (+)-9-RispOH, resulting in 100% of enantiomeric excess. The Cunninghamella elegans fungus was also able to stereoselectively biotransform risperidone into (+)- and (-)-9-RispOH enantiomers at different rates. (C) 2012 Elsevier B.V. All rights reserved.

World Federation of Societies of Biological Psychiatry (WFSBP) Guidelines for Biological Treatment of Schizophrenia, Part 1: Update 2012 on the acute treatment of schizophrenia and the management of treatment resistance

These updated guidelines are based on a first edition of the World Federation of Societies of Biological Psychiatry Guidelines for Biological Treatment of Schizophrenia published in 2005. For this 2012 revision, all available publications pertaining to the biological treatment of schizophrenia were reviewed systematically to allow for an evidence-based update. These guidelines provide evidence-based practice recommendations that are clinically and scientifically meaningful and these guidelines are intended to be used by all physicians diagnosing and treating people suffering from schizophrenia. Based on the first version of these guidelines, a systematic review of the MEDLINE/PUBMED database and the Cochrane Library, in addition to data extraction from national treatment guidelines, has been performed for this update. The identified literature was evaluated with respect to the strength of evidence for its efficacy and then categorised into six levels of evidence (A-F; Bandelow et al. 2008b, World J Biol Psychiatry 9: 242). This first part of the updated guidelines covers the general descriptions of antipsychotics and their side effects, the biological treatment of acute schizophrenia and the management of treatment-resistant schizophrenia.