Publications by authors named "U Riechert"

Charging of insulators modifies local electric field distribution and increases potential threat to the safety of the gas insulated equipment. In this paper, surface charge tailoring techniques are classified and reviewed by introducing a Dam-flood model. Technical solutions of different charge tailoring methods are compared and discussed.

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Induction of Hsp70 in the brain has been reported after intake of drugs of abuse like amphetamine and lysergic acid diethylamide. In this investigation, gene expression of Hsp70 and other heat shock genes in the rat brain was studied in response to morphine. Twenty milligrams per kilogram morphine intraperitoneally resulted in a marked induction of Hsp70 messenger RNA (mRNA) expression in the frontal cortex with a maximum increase of 13.

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Multiple approaches have been performed to elucidate the molecular mechanisms underlying drug withdrawal in opioid-dependent animals. Opiate withdrawal represents a state of neuronal hyperexcitability in the brain that leads to alterations in a number of second-messenger systems which, in turn, induce expression of transcription factors. Whereas earlier studies have primarily demonstrated an early and transient transcriptional activation of members of the Fos, Jun, and Krox families, recent microarray studies investigating the delayed response could additionally identify several transcriptional repressors such as cAMP response element modulator (CREM), IkappaB, silencer factor B, helix-loop-helix proteins, or glucocorticoid-induced leucine zipper, indicating the attempt of the brain to re-establish homeostasis after withdrawal-induced excitation.

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Opioid dependence may be associated with adaptive changes in gene expression in the brain. In the present study we used DNA microarrays (U34A; Affymetrix) to analyze the expression of about 8000 genes in the frontal cortex of rats chronically treated with morphine and in rats after naloxone precipitated withdrawal. Chronic treatment for 10 days with ascending doses of morphine (10-50 mg/kg twice daily) resulted in a more than twofold induction of 14 genes after the last injection of morphine.

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Numerous stimuli induce immediate early gene (IEG) expression in neurones, but a comprehensive overview of the late-response genes is lacking. Therefore we aimed to identify changes in the neuronal gene expression profile following intense stimulation. Forskolin and 12-O-tetradecanoylphorbol-13-acetate (TPA), direct activators of intracellular second messengers, were applied to primary cultured cortical neurones.

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