Alpha-haemolysin of uropathogenic E. coli induces Ca2+ oscillations in renal epithelial cells

Pyelonephritis is one of the most common febrile diseases in children. If not treated appropriately, it causes irreversible renal damage and accounts for a large proportion of end stage renal failures. Renal scarring can occur in the absence of inflammatory cells, indicating that bacteria may have a direct signalling effect on renal cells. Intracellular calcium ([Ca2+]i) oscillations can protect cells from the cytotoxic effects of prolonged increases in intracellular calcium. However, no pathophysiologically relevant protein that induces such oscillations has been identified. Here we show that infection by uropathogenic Escherichia coli induces a constant, low-frequency oscillatory [Ca2+]i response in target primary rat renal epithelial cells induced by the secreted RTX (repeats-in-toxin) toxin alpha-haemolysin. The response depends on calcium influx through L-type calcium channels as well as from internal stores gated by inositol triphosphate. Internal calcium oscillations induced by alpha-haemolysin in a renal epithelial cell line stimulated production of cytokines interleukin (IL)-6 and IL-8. Our findings indicate a novel role for alpha-haemolysin in pyelonephritis: as an inducer of an oscillating second messenger response in target cells, which fine-tunes gene expression during the inflammatory response.     

Lectin-induced lymphocyte stimulation in pigs — a kinetic study of NORs

Summary Early reactions of rRNA-cistrons in lectin-stimulated PBL cultures of domestic pigs are shown. Interphases showing 3 or more clusters of stained areas were attributed mainly to cells after first division. Clear differences are shown between PHA-and ConA-induced NOR-expression patterns compared to the patterns in PW-stimulated cultures.We thank Dr W. Gratze for valuable techniqual assistance, Dr M. Kundi from the Institute of Environmental Health of the University of Vienna for the statistical treatment of our data and the Ludwig Boltzmann Society for financial support.     

Die teratogene Wirkung von Äthylharnstoff und Nitrit bei Ratten

Summary Simultaneous peroral application of ethylurea and sodium nitrite to pregnant Sprague-Dawley rats, on the 9th and 10th days of gestation, causes embryotoxic and/or teratogenic effects. Each substance alone does not afflict the fetuses, whereas the combined addition to the food permits the formation of ethyl nitroso-urea in the digestive tract. The latter readily passes the placenta and develops the teratogenic effect. It is to be considered that teratogenic substances can occur from food constituents in the human organism also.     

Divergent effects of theophylline on adenylate cyclase preparations from guinea-pig heart and lung

Zusammenfassung Theophyllin verringert die Aktivität der Adenyl-Cyclase (AC) in der plasmamembranreichen Fraktion der Meerschweinchenlunge in Konzentrationen von 6–10 mM; es hat dagegen keinen Einfluss auf die Aktivität der AC in Meerschweinchenherzen. Diese Resultate weisen darauf hin, dass in verschiedenen Geweben geringe Unterschiede in der Enzym-Katalyse bestehen können.     

Intracerebroventricular angiotensin II increases arterial blood pressure in rhesus monkeys by stimulation of pituitary hormones and the sympathetic nervous system

Summary Intracerebroventricular injections of angiotensin II in anesthetized rhesus monkeys increase systemic blood pressure and heart rate. These effects are accompanied by an increase in plasma ADH, cortisol, adrenaline and noradrenaline. Angiotensin II may participate in central mechanisms of blood pressure regulation by its stimulatory effect on the sympathetic nervous system, on ADH and on ACTH release in primates.     

Abtransport von Schwefelverbindungen aus Bohnenprimärblättern (Phaseolus vulgaris) nach Begasung mit H2 35S

Summary Some unnatural sulphur amino acids can be detected in the phloem of the vascular bundles from Phaseolus vulgaris after the application of H₂ ³⁵S to the primary leaves.     

Der erythrocytäre Magnesiumstoffwechsel bei intakter und kälteinhibierter Glykolyse

Summary Continuation of glycolysis in human erythrocytes by incubation of heparinized whole blood at 37°C is followed by a decrease in the Mg-content of red cells. On inhibition of glycolysis by cold (4°C), the Mg-content of erythrocytes remains unaltered or, often, slightly increases. These actions are in clear contrast to the behaviour of potassium ions under the same conditions.