Cytotoxic necrotizing factor from Escherichia coli induces RhoA-dependent expression of the cyclooxygenase-2 gene

Cytotoxic necrotizing factor 1 (CNF) is a toxin produced by some isolates of Escherichia coli that cause extraintestinal infections. CNF can initiate signaling pathways that are mediated by the Rho family of small GTPases through a covalent modification that results in constitutive activation. In addition to regulating the assembly of actin stress fibers and focal adhesion complexes, RhoA can also regulate gene expression at the level of transcription. Here we demonstrate for the first time, by using a luciferase-based reporter system, that the transcription of cyclooxygenase-2 (COX-2) is strongly upregulated in NIH 3T3 fibroblasts treated with CNF and that this effect is dependent upon the activation of RhoA by the toxin. Subsequent protein tyrosine phosphorylation events modulate the induction, but the transcription signal is not mediated by Rho-associated kinase (p160/ROCK) and so must rely upon another effector that is activated by RhoA. CNF therefore induces COX-2 expression via a RhoA-dependent signaling pathway that diverges from the pathway that regulates cytoskeletal rearrangements in response to RhoA activation

Sex Differences and Similarities in Urban Home Ranges and in the Accuracy of Cognitive Maps

Former research has examined potential human sex differences in spatial abilities or home range size. Both are assumed to have an adaptive function. In this study we combined the investigation of home range size in an urban environment and spatial abilities by accuracy analysis of cognitive maps. Participants ( n = 87) drew a sketch of their home range in Vienna depicting all places regularly visited in every-day life. We used the sketches' geographical locations to calculate the size of the home range. With the Geometric Morphometric Methodology, we quantified the accuracy of cognitive maps by measuring Euclidean distances between corresponding landmarks in the sketches and the geographical maps of home ranges. Our results showed a non-significant trend for men to have a larger home range. Overall, participants' cognitive maps were fairly accurate. However, men sketched their home range more precisely than women. Female map accuracy increased as a function of residency duration. In addition, accuracy of cognitive maps was influenced by home range size and number of frequently visited places. In summary, findings indicate that sex differences in home range size and spatial abilities may still persist in humans living in urbanized Western societies, but are also influenced by environmental experience

Development of in-line plutonium solution NDA instrumentation at the Savannah River Plant

A K-absorption-edge plutonium solution densitometer has been developed by the Los Alamos Scientific Laboratory for in-line test and evaluation in the process line at the Savannah River Plant. The design features of the measurement system, the measurement principles, and performance data are presented