Stimulation of HeLa cell growth by physiological concentrations of 4-hydroxynonenal

The aim of this study was to analyze the growth response of HeLa cells over a prolonged period of time to a single exposure of physiological and supraphysiological concentrations of 4-hydroxynonenal (HNE), a peroxidation product of omega-6-polyunsaturated fatty acids. Furthermore, the growth modulating effect of serum factors, particularly albumin, on the growth pattern was examined. The effects of HNE on the growth rate and viability of the cells, as well as on the incorporation of labelled amino acids were monitored daily over a period of four days. Fetal calf serum not only had a growth stimualting effect but also modulated the action of HNE. In neither respect was albumin able to substitute for serum indicating that the influence of serum was not exerted via an albumin–HNE conjugate. HNE had a clear dose-dependent effect and a distinction could be made between a supraphysiological concentration (100 μM), which was primarily cytotoxic and a physiological range (below 10 μM) which showed growth modulatory effects. These effects consisted of a transient inhibition in the initial phase of the cell growth, which under optimal conditions (in presence of serum) was followed by a period of increased proliferation, compared to untreated control cultures, until confluence was attained. It is suggested that HNE is not only a toxic product of lipid peroxidation, but a physiological growth regulating factor as well.     

Measuring ecological impact of water consumption by bioethanol using life cycle impact assessment

Purpose  

Though the development of biofuel has attracted numerous studies for quantifying potential water demand applying life cycle thinking, the impacts of biofuel water consumption still remain unknown. In this study, we aimed to quantify ecological impact associated with corn-based bioethanol water consumption in Minnesota in responding to different refinery expansion scenarios by applying a life cycle impact assessment method.     

Morphometric studies of prepyramidal and pyramidal neurons of various vertebrates]

Praepyramidal and pyramidal neurons were demonstrated in homologous telencephalic areas of Salmo irideus (Gibbons 1855), Rana temporaria L., Rattus norvegicus, forma alba, by means of the Golgi-technique. A comparative morphometrical analysis was made concerning the following parameters: main dendritic length, length of the pericaryon, number of dendritic spines in the first 50-micrometer-dendritic segment and length of the spines-free zone. From these data a quotient was calculated and expressing the theoretical dendritic length per ten spines. There is an increase of length of the pericaryon, length of the spines-free zone, main dendritic length and a pseudo-decrease of the number of dendritic spines in the first 50 micrometer-dendritic segment in rats, as compared with Rana and Salmo. The results are discussed with respect to following problems: homology, phylogenesis and corticalisation.