Learn More
As recently reported, the synthetic cannabinoid JWH-018 is the subject of extensive phase I and II metabolic reactions in vivo. Since these studies were based on LC-MS/MS and/or GC-MS identification and characterisation of analytes, the explicit structural assignment of the metabolites was only of preliminary nature, if possible at all. Here, we report the(More)
The number of compounds and doping methods in sports is in a state of constant flux. In addition to 'traditional' doping agents, such as anabolic androgenic steroids or erythropoietin, new therapeutics and emerging drugs have considerable potential for misuse in elite sport. Such compounds are commonly based on new chemical structures, and the mechanisms(More)
Increasing the blood's capacity for oxygen transport by erythropoiesis-stimulating agents (ESAs) constitutes a prohibited procedure of performance enhancement according to the World Anti-Doping Agency (WADA). The advent of orally bio-available small-molecule ESAs such as hypoxia-inducible factor (HIF) stabilizers in the development of novel anti-anaemia(More)
The study of the collision-induced dissociation behavior of various substituted isoquinoline-3-carboxamides, which are amongst a group of drug candidates for the treatment of anemic disorders (e.g., FG-2216), allowed for the formulation of the general mechanisms underlying the unusual fragmentation behavior of this class of compounds. Characterization was(More)
Reactive oxygen species (ROS) as well as matrix metalloproteinases (MMPs) induce modifications in the tight junction (TJ) protein occludin which is crucial for the blood-brain barrier (BBB) function. We investigated the role of ROS and MMPs in endothelial autoregulatory response on oxidative stress with respect to occludin and the BBB integrity. The ROS(More)
AICAR (5-amino-4-imidazolecarboxyamide ribonucleoside) arguably provides performance-enhancing properties even in the absence of physical exercise and, therefore, the substance is banned in elite sports since 2009. Due to the natural presence of AICAR in human blood and urine, uncovering the misuse by direct qualitative analysis is not possible. Entering(More)
RATIONALE Clenbuterol (4-amino-α-[(tert-butylamino)methyl]-3,5-dichlorobenzyl alcohol) is approved for human and veterinary use primarily for the treatment of pulmonary afflictions. Despite the authorized administration in cases of medical indications, the misuse of clenbuterol in animal husbandry as well as elite and amateur sport has frequently been(More)
Influencing the endurance in elite sports is one of the key points in modern sports science. Recently, a new class of prohibited substances reached in the focus of doping control laboratories and their misuse was classified as gene doping. The adenosine monophosphate activated protein kinase activator 5-amino-4-imidazolecarboxyamide ribonucleoside (AICAR)(More)
Hypoxia-inducible factor (HIF) stabilizers increase blood haemoglobin levels after oral administration and their use in sports was recently banned by the World Anti-Doping Agency. For the support of analytical assay development, the metabolic fate of two model HIF stabilizers, based on the isoquinoline-3-carboxamide scaffold of the lead drug candidate(More)
Structure elucidation of steroids by mass spectrometry has been of great importance to various analytical arenas and numerous studies were conducted to provide evidence for the composition and origin of (tandem) mass spectrometry-derived product ions used to characterize and identify steroidal substances. The common product ion at m/z 97 generated from(More)