An assay for dopamine-β-hydroxylase activity in tissues and serum

Zusammenfassung Eine isotopische Methode zur Bestimmung der DH-Aktivität wird beschrieben. Die Methode wurde verwendet zur Bestimmung der DH-Aktivität im menschlichen Serum und in verschiedenen Organen der Ratte. Das sympatische Nervensystem des Menschens kann mit dieser Methode weiter erforscht werden.

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This work was supported by USPHS Grant No. 5 R01 MH-02717-12.     

RNA-dependent RNA polymerase encoded by hepatitis C virus: biomedical applications

The hepatitis C viruses (HCVs) are a group of small enveloped RNA viruses that have been viewed as a leading cause of chronic hepatitis in humans. Infections by HCV represent a serious global health problem, because millions of people worldwide are infected and no efficient treatment is available at the present time. Since HCV was identified in 1989, considerable effort has been devoted to the discovery and development of novel molecules to treat HCV-related diseases. One of the approaches is the development of novel inhibitors that interrupt the normal functions of HCV NS5B, an RNA-dependent RNA polymerase essential to HCV replication. This review summarizes recent advances in the biochemical and structural understanding of HCV NS5B polymerase as well as in the development of antiviral agents targeting this important enzyme. Received 19 March 2002; received after revision 23 April 2002; accepted 23 April 2002     

Mantle compensation of active metamorphic core complexes at Woodlark rift in Papua New Guinea

In many highly extended rifts on the Earth, tectonic removal of the upper crust exhumes mid-crustal rocks, producing metamorphic core complexes. These structures allow the upper continental crust to accommodate tens of kilometres of extension, but it is not clear how the lower crust and underlying mantle respond. Also, despite removal of the upper crust, such core complexes remain both topographically high and in isostatic equilibrium. Because many core complexes in the western United States are underlain by a flat Moho discontinuity, it has been widely assumed that their elevation is supported by flow in the lower crust or by magmatic underplating. These processes should decouple upper-crust extension from that in the mantle. In contrast, here we present seismic observations of metamorphic core complexes of the western Woodlark rift that show the overall crust to be thinned beneath regions of greatest surface extension. These core complexes are actively being exhumed at a rate of 5-10 km Myr(-1), and the thinning of the underlying crust appears to be compensated by mantle rocks of anomalously low density, as indicated by low seismic velocities. We conclude that, at least in this case, the development of metamorphic core complexes and the accommodation of high extension is not purely a crustal phenomenon, but must involve mantle extension.