Historical reconstruction of sturgeon (Acipenser spp.) spatiotemporal distribution and causes for their decline in North-Western Europe

Biodiversity and Conservation - This study aims to reconstruct the historical spatiotemporal distribution of the anadromous sturgeons, Acipenser sturio and A. oxyrinchus, in NW-Europe (especially...     

Enantiomeric resolution of galanthamine and related drugs used in anti-Alzheimer therapy by means of capillary zone electrophoresis employing derivatized cyclodextrin selectors

An analytical assay is presented for the determination of the enantiomeric composition of galanthamine and related synthetic and natural compounds. (−)-Galanthamine is isolated from Galanthus nivalis and is used in this optical pure form in the therapy of Alzheimer’s disease. Recent efforts for a total synthesis of unichiral (−)-galanthamine is connected with the need for a fast and reliable assay for the determination of the optical purity of the end product, as well as for optimizing and controlling the final steps in total synthesis particularly the asymmetric transformation of narwedine. In this paper the enantiomeric resolution of these compounds is reported employing a capillary electrophoretic system with β-cyclodextrin derived chiral selectors. With the proposed system a number of galanthamine and narwedine derived analogous compounds could be separated, including 1-bromo- and N-alkyl-substituted compounds.     

The labour pains of biochemical selenology: The history of selenoprotein biosynthesis

The serendipitous discoveries leading to the present knowledge on selenium's role in biology are reviewed. Detected in 1818 as by-product of sulphuric acid production, selenium first attracted medical attention as an industrial hazard. In parallel selenium intoxication was recognized as cause of life stock diseases. Reports on teratogenic effects and carcinogenicity of selenium followed since the middle of the past century. In 1954 first hints towards specific biological functions of selenium were contributed from microbiology, and its essentiality for mammalian life was discovered in 1957. Independent and unrelated studies led to the identification of selenium as an integral constituent of one mammalian and two bacterial enzymes in the early 70ies followed by the identification of selenocysteine in these proteins. In the 80ies, independent sequencing of selenoproteins and cloned DNAs revealed that the selenocysteine of selenoproteins is encoded by the termination codon TGA (UGA). Recoding of TGA as selenocysteine codon by secondary mRNA structures was first elucidated by molecular genetics in bacteria and later in mammals. During the 90ies, finally, the basic principles of selenoprotein synthesis were worked out by molecular biology tools. The article closes with spotlight comments on proven and potential biomedical benefits of selenium and related research deficits.     

Dynamic Suppression of Average Facial Structure Shapes Neural Tuning in Three Macaque Face Patches

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