Evidence against a requirement for phospholipid methylation in adenylate cyclase activation by hormones. Methyltransferase inhibitors do not impair cyclic AMP accumulation induced by glucagon or beta-adrenergic agents in rat hepatocytes

Several observations made in the fungus Podospora anserina suggest that translational ambiguity may increase, and possibly must increase, at specific stages of the life cycle. Such changes in the properties of the translational apparatus seem to occur as well in the yeast S. cerevisiae and in the alga C. reinhardii. A slight increase of the misreading level would allow readthrough or frameshifting necessary to synthesise regulatory proteins in low amount at key points of cellular differentiation.     

Protection of heat induced cytoxicity by glycerol

Glycerol, at concentrations of 2–10% is a potent hyperthermic (43°–45°C) protector of cultured Chinese hamster cells, V79. Furthermore, the sensitization effect of low pH on heat death is also drastically reduced by the addition of glycerol into the culture medium. Together with the known cellular effects of heat and the role of glycerol in various cellular structures and functions, the data suggest that microtubules and membranes may be involved in the expression of heat-induced cell death.     

Protein assay in reversed micelle solutions

Summary An adaptation of the Lowry (1951) method has been developed for quantifying proteins in organic reversed micellar solutions. Ethanol is added to improve the re-extraction of the proteins from the micelles and a centrifugation step is included to separate the organic phase.     

Production and rheological characterization of the viscoelastic biopolymer produced by an eel epithelial cell line

The production and the characterization of the viscoelastic biopolymer from an eel epithelial cell line were investigated in this study. The kinetics of the cell growth and the biopolymer production were firstly examined. The rheological information for the biopolymer produced was provided by three modes of viscoelastic measurements, including flow, creep and oscillatory tests. The effect of pH and temperature on the rheological properties of the biopolymer was also evaluated.     

Anaerobic metabolism of l-phenylalanine via benzoyl-CoA in the denitrifying bacterium Thauera aromatica

The anaerobic metabolism of phenylalanine was studied in the denitrifying bacterium Thauera aromatica, a member of the β-subclass of the Proteobacteria. Phenylalanine was completely oxidized and served as the sole source of cell carbon. Evidence is presented that degradation proceeds via benzoyl-CoA as the central aromatic intermediate; the aromatic ring-reducing enzyme benzoyl-CoA reductase was present in cells grown on phenylalanine. Intermediates in phenylalanine oxidation to benzoyl-CoA were phenylpyruvate, phenylacetaldehyde, phenylacetate, phenylacetyl-CoA, and phenylglyoxylate. The required enzymes were detected in extracts of cells grown with phenylalanine and nitrate. Oxidation of phenylalanine to benzoyl-CoA was catalyzed by phenylalanine transaminase, phenylpyruvate decarboxylase, phenylacetaldehyde dehydrogenase (NAD⁺), phenylacetate-CoA ligase (AMP-forming), enzyme(s) oxidizing phenylacetyl-CoA to phenylglyoxylate with nitrate, and phenylglyoxylate:acceptor oxidoreductase. The capacity for phenylalanine oxidation to phenylacetate was induced during growth with phenylalanine. Evidence is provided that α-oxidation of phenylacetyl-CoA is catalyzed by a membrane-bound enzyme. This is the first report on the complete anaerobic degradation of an aromatic amino acid and the regulation of this process. Received: 6 March 1997 / Accepted: 16 May 1997     

MedataWeb: A shared platform for multimodality medical images and Atlases

Computer-assisted medical interventions and treatment planning have known an increasing interest and research activity in different fields and applications. However, before the routine deployment of these procedures becomes a reality, in vivo and in silico validations must be undertaken. This paper describes a platform containing multimodality medical images and atlases useful for algorithms evaluation, comparison and validation. The platform contains des-identified data (images, contours and atlases) from the ProstateAtlas and ProstateWeb project: the first morphological and zonal atlas of the prostate, and from clinical data of lymphoma PET (PETWeb). Data are available at the URL: http://www.medataweb.U703.net.