Publications by authors named "Bursch W"

Background: Intoxication with Amanita phalloides is associated with high morbidity and mortality. Treatment therapies include general support, toxin elimination, pharmacotherapy with agents such as the hepatoprotective agent silibinin, and, in extreme states, liver transplantation. Despite these therapeutic interventions, mortality remains relatively high.

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Metaxya rostrata C. Presl (Metaxyaceae) is a common tree fern in Central and South America that is used for the treatment of intestinal ulcers and tumours in ethnic medicine. Using a bioactivity-guided strategy 2-deprenyl-rheediaxanthone B (XB) has been isolated as one of the active principles in this plant.

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In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding.

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Glutathione S-transferases (GSTs) play an essential role in the elimination of xenobiotic-derived electrophilic metabolites and also catalyze certain steps in the conversion of endogenous molecules. Their expression is controlled by different transcription factors, such as the antioxidant-activated Nrf2 or the constitutive androstane receptor. Here, we show that the Wnt/beta-catenin pathway is also involved in the transcriptional regulation of GSTs: GSTm2, GSTm3, and GSTm6 are overexpressed in mouse hepatomas with activating Ctnnb1 (encoding beta-catenin) mutations and in transgenic hepatocytes expressing activated beta-catenin.

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The elimination of tumor cells by apoptosis is the main mechanism of action of chemotherapeutic drugs. More recently, autophagic cell death has been shown to trigger a nonapoptotic cell death program in cancer cells displaying functional defects of caspases. Fenretinide (FenR), a synthetic derivative of retinoic acid, promotes growth inhibition and induces apoptosis in a wide range of tumor cell types.

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Research in autophagy continues to accelerate,(1) and as a result many new scientists are entering the field. Accordingly, it is important to establish a standard set of criteria for monitoring macroautophagy in different organisms. Recent reviews have described the range of assays that have been used for this purpose.

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Cytostatic agents are applied in cancer therapy and subsequently excreted into hospital wastewater. As these substances are known to be carcinogenic, mutagenic and toxic for reproduction, they should be removed from wastewater at their source of origin. In this study the fate and effects of the cancerostatic platinum compounds (CPC) cisplatin, carboplatin, oxaliplatin, 5-fluorouracil (5-FU) and the anthracyclines doxorubicin, daunorubicin and epirubicin were investigated in hospital wastewater.

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MCF-7 cells undergo autophagic death upon tamoxifen treatment. Plated on non-adhesive substratum these cells died by anoikis while inducing autophagy as revealed by monodansylcadaverine staining, elevated light-chain-3 expression and electron microscopy. Both de novo and anoikis-derived autophagic dying cells were engulfed by human macrophages and MCF-7 cells.

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Activins are a closely related subgroup within the TGFbeta superfamily of growth and differentiation factors. They consist of two disulfide-linked beta subunits. Four mammalian activin beta subunits termed beta(A), beta(B), beta(C), and beta(E), respectively, have been identified.

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Autophagy constitutes a fundamental survival strategy of cells; its disturbance contributes to the pathogenesis of cancer, liver and immune disease, pathogen infection, myopathies as well as neurodegenerative disorders such as Amyotrophic lateral sclerosis, Parkinson;s, Huntington;s and Alzheimer;s disease. The pathogenesis of neurodegenerative diseases also involves a gradual and progressive loss of neuronal cells. Cells may use different pathways for active self-destruction as reflected by different morphology: while in apoptosis (or "type I") nuclear fragmentation associated with cytoplasmic condensation but preservation of organelles is predominant, autophagic degradation of the cytoplasmic structures preceding nuclear collapse is a characteristic of a second type of programmed cell death (PCD).

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In short-term in vivo experiments, liver growth and regression in mice with high (C3H/He), intermediate (B6C3F1) or low (C57BL/6J) susceptibility to hepatocarcinogenesis was compared. Liver growth was induced by dietary administration of phenobarbital (PB; 750 ppm) or nafenopin (NAF; 500 ppm). PB or NAF treatment for 7 days produced moderate increases of liver DNA (15% or 25-28%, respectively) along with pronounced hypertrophy.

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C3H/He and B6C3F1 show much higher liver cancer susceptibility than C57BL/6J mice. We studied the hypothesis that this difference might result from failure of apoptosis. Hepatocarcinogenesis was induced by a single dose of N-nitrosodiethylamine (NDEA), followed by phenobarbital (PB) for up to 90 weeks.

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A consortium of Austrian scientists (ARCEM) carried out a multidisciplinary environmental study on Austrian surface and ground waters including chemical monitoring, bioindication, risk assessment and risk management for selected endocrine disrupters: 17beta-estradiol, estriol, estrone, 17alpha-ethinylestradiol, 4-nonylphenol, 4-nonylphenol ethoxylates (4-NP1EO, 4-NP2EO) and their degradation products, ocytlphenol, ocytlphenol ethoxylates (OP1EO, OP2EO) as well as bisphenol A. To obtain data representative for Austria, a material flow analysis served to select relevant compounds and water samples were collected monthly over one year at those sites routinely used in Austrian water quality control. The following results were obtained and conclusions drawn: 1.

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Cells use different pathways for active self-destruction as reflected by different morphology: while in apoptosis (or "type I") nuclear fragmentation associated with cytoplasmic condensation but preservation of organelles is predominant, autophagic degradation of cytoplasmic structures preceding nuclear collapse is a characteristic of a second type of programmed cell death (PCD). The diverse morphologies can be attributed--at least to some extent--to distinct biochemical and molecular events (e.g.

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Apoptosis constitutes one of the organisms defense lines against cancer. We investigated whether failure of apoptosis may be concurrently causative for the high cancer susceptibility in C3H/He as compared to C57BL/6J mice (low cancer susceptibility). First, in short-term in vivo experiments (7-21 days), mouse liver growth (C3H/He, C57BL/6J) was induced by administration of phenobarbital (PB; 2 days 500 ppm + 5 days 750 ppm via the food) or nafenopin (NAF; 7 days 500 ppm via the food), cessation of PB or NAF treatment served to initiate liver involution.

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In our study we tested the utility of antibodies that specifically recognize the cleaved large (active) subunits of caspase-3 and caspase-9 for immunohistochemical detection of apoptotic hepatocytes in rat liver sections using archival material from cyproterone acetate (CPA)-treated and control rats. CPA blocks apoptosis of hepatocytes and discontinuation of CPA treatment results in a syncronized wave of hepatocyte apoptosis. By comparing liver sections from CPA-treated and control rats with high and low rates of apoptosis we observed a close correlation between the occurrence of cleaved caspase-positive apoptotic figures and H&E-stained apoptotic bodies when evaluated in parallel sections.

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Purpose: In the liver, transforming growth factor beta-1 (TGF-beta1) constitutes a major negative growth regulating factor involved in the control of cell numbers; failure of this control mechanism has been associated with the development of liver cancer. Since no reports on the in vivo effects of exogenously administered TGF-beta1 on apoptosis in liver tumors have been published yet, we studied hepatocyte sensitivity to the proapoptotic action of TGF-beta1 in stages of chemically induced mouse liver carcinogenesis.

Methods: Mouse liver carcinogenesis was initiated by a single dose of N-nitrosodiethylamine (NDEA, 90 mg/kg b.

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The occurrence of cell death as a physiological event in multicellular organisms has been known for more than 150 years; in 1972 the term apoptosis was introduced on morphological grounds. However, accumulating evidence suggests that programmed cell death (PCD) is not confined to apoptosis, but that cells use different pathways for active self-destruction as reflected by different morphology: condensation prominent, type I or apoptosis; autophagy prominent, type II; etc. Autophagic PCD appears to be a phylogenetically old phenomenon; it may occur in physiological and disease states.

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The fate of cytosolic proteins was studied during Fas-induced cell death of Jurkat T-lymphocytes by proteome analysis. Among 1000 spots resolved in two-dimensional gels, comparison of control versus apoptotic cells revealed that the signal intensity of 19 spots decreased or even disappeared, whereas 38 novel spots emerged. These proteins were further analyzed with respect to de novo protein synthesis, phosphorylation status, and intracellular localization by metabolic labeling and analysis of subcellular protein fractions in combination with two-dimensional Western blots and mass spectrometry analysis of tryptic digests.

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Programmed cell death comprises several subtypes, as revealed by electron microscopy. Apoptosis or type I programmed cell death is characterized by condensation of cytoplasm and preservation of organelles, essentially without autophagic degradation. Autophagic cell death or type II programmed cell death exhibits extensive autophagic degradation of Golgi apparatus, polyribosomes and endoplasmatic reticulum, which precedes nuclear destruction.

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