Sven Gottschalk

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The therapeutic efficacy of imatinib mesylate (Gleevec) is based on its specific inhibition of the BCR-ABL oncogene protein, a widely expressed tyrosine kinase in chronic myelogenous leukemia (CML) cells. The goal of this study was to evaluate glucose metabolism in BCR-ABL-positive cells that are sensitive to imatinib exposure. Two human BCR-ABL-positive(More)
Cell-penetrating peptides (CPPs) may have impli-cations in biomedical sciences by improving the delivery of a wide variety of drugs through the membrane barrier. CPPs are generally taken up by endocytotic pathways, and vesicular encapsulation is a limiting factor in the area of intracellular targeting. A novel, cationic cysteine-rich CPP, CyLoP-1, has been(More)
Co-administration of the calcineurin inhibitor cyclosporine and the mTOR inhibitors sirolimus or everolimus increases the efficacy of immunosuppression after organ transplantation. However, clinical studies showed enhancement of cyclosporine toxicity. To characterize the biochemical mechanisms involved, we assessed the time-dependent effects of cyclosporine(More)
Quantification of tumor necrosis in cancer patients is of diagnostic value as the amount of necrosis is correlated with disease prognosis and it could also be used to predict early efficacy of anti-cancer treatments. In the present study, we identified two near infrared fluorescent (NIRF) carboxylated cyanines, HQ5 and IRDye 800CW (800CW), which possess(More)
Hepatocyte death due to apoptosis is a hallmark of almost every liver disease. Manipulation of cell death regulatory steps during the apoptotic process is therefore an obvious goal of biomedical research. To clarify whether metabolic changes occur prior to the characteristic apoptotic events, we used ex vivo multinuclear NMR-spectroscopy to study metabolic(More)
In vitro 1H- and 13C-NMR spectroscopy was used to investigate the effect of ammonia on fatty acid synthesis and composition in cultured astrocytes. Cells were incubated 3 and 24 h with 5 mM ammonia in the presence or absence of the glutamine synthetase inhibitor methionine sulfoximine. An increase of de novo synthesized fatty acids and the glycerol subunit(More)
Nanosecond-duration laser pulses are exploited in a plethora of therapeutic and diagnostic applications, such as optoacoustic imaging. However, phototoxicity effects of pulsed radiation in living cells, in particular those expressing genetic reporters, are not well understood. We established a three-dimensional fluorescent protein expressing cellular model(More)
A series of bimodal metabotropic glutamate-receptor targeted MRI contrast agents has been developed and evaluated, based on established competitive metabotropic Glu receptor subtype 5 (mGluR5) antagonists. In order to directly visualize mGluR5 binding of these agents on the surface of live astrocytes, variations in the core structure were made. A set of(More)
Introduction: Brain edema is a major cause of death of patients with Hepatic Encephalopathy (HE) due to acute liver failure (ALF). Hyperammonemia is considered to be a key factor leading to brain edema in ALF. In the brain, the astrocytic enzyme glutamine synthetase (GS) is uniquely responsible for converting ammonia into glutamine. It has been the(More)
Responsive or smart contrast agents (SCAs) represent a promising direction for development of novel functional MRI (fMRI) methods for the eventual noninvasive assessment of brain function. In particular, SCAs that respond to Ca(2+) may allow tracking neuronal activity independent of brain vasculature, thus avoiding the characteristic limitations of current(More)