Clemens Guenther

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The family of VEGF receptors are important mediators of angiogenesis, which is essential for tumour growth and metastasis. PTK/ZK is a multiple VEGF receptor inhibitor that blocks the activity of all known VEGF receptor tyrosine kinases. This phase I/II trial evaluated the safety, pharmacokinetics and efficacy of PTK/ZK in patients with liver metastases(More)
Six healthy, elderly volunteers received three topical treatments with Advantan lotion containing 0.1% of methylprednisolone aceponate (MPA, CAS 86401-95-8) on intact, inflamed and stripped skin in a consecutive fashion at weekly intervals. The lotion (O/W emulsion) containing 14C-MPA (specific radioactivity 1.8 MBq/mg MPA) was applied in an area dose of 5(More)
Purpose. Highly lipophilic basic drugs, the antiestrogens AE 1 (log P = 5.82) and AE 2 (log P = 7.8) shall be delivered transdermally. Methods. Transdermal permeation of drugs, enhancers, and solvents from various fluid formulations were characterized by in-vitro permeation studies through excised skin of hairless mice. Furthermore, differential scanning(More)
Vatalanib (PTK787/ZK-222584) is a new oral antiangiogenic molecule that inhibits all known vascular endothelial growth factor receptors. Vatalanib is under investigation for the treatment of solid tumors. Disposition and biotransformation of vatalanib were studied in an open-label, single-center study in patients with advanced cancer. Seven patients were(More)
PTK/ZK is a novel, oral angiogenesis inhibitor that specifically targets all 3 vascular endothelial growth factor (VEGF) receptor tyrosine kinases and is currently in phase III clinical trials. In early clinical trials, PTK/ZK demonstrated a dose-dependent reduction in tumor vascular parameters as measured by dynamic contrast-enhanced magnetic resonance(More)
Transdermal systems (TDS) are a well-known application form for small, moderately lipophilic molecules. The aim of this study was to investigate the possibility of applying a highly lipophilic drug, the antiestrogen AE (log P=5.82) transdermally by polyacrylate-based matrix TDS. For this purpose, two effects of both drug and enhancer concentration in TDS(More)
The aim of this study was to develop matrix-type transdermal systems (TDSs) containing the highly lipophilic (log P = 5.82) antiestrogen (AE) and the permeation enhancers propylene glycol and lauric acid. For that purpose, permeation of AE from various adhesive matrices through excised skin of hairless mice was evaluated. It was found that pretreatment of(More)
Purpose. The aim of this study was to enhance the transdermal absorption of the highly active progestin gestodene from matrix type transdermal delivery systems (TDDS) by formation of prodrugs with improved matrix solubility. Methods. Gestodene esters were synthesized via acylation of the drug with the respective carboxylic anhydrides. Subsequently TDDS were(More)
-The number of fluctuating energy sources in the power grid increases continuously. Simultaneously the importance of electrical energy storage increases. Batteries are one promising possibility for short-term storage. In this work a mathematical impedance model of a Lithium-ion battery with high dynamics for simulation of loads due to driving cycles and(More)
Radioluminography (RLG) was applied for the quantitation of (125)iodine ((125)I) autoradiograms using the bioimaging analyzer BAS 2000. RLG was performed on 50-microm sections of sagittal whole-body sections of rats and (125)I-radiolabeled erythrocyte calibration scales. Linearity, sensitivity, accuracy, and reproducibility were investigated in comparison(More)