Perylene and copper in the sediments could be identified as potential causes of the genotoxic response. To compare the results (maximum induction coefficients) of zebrafish embryos with an established comet protocol, rainbow trout liver cells (RTL-W1) were exposed to the same extracts. The findings correlated well (Spearman correlation r=0.90), proving a good reliability of the results from zebrafish primary cells. In conclusion, the present study demonstrates that the bioavailable fraction of the genotoxic pollutants may pose a threat for both benthic organisms and human health via drinking-water and fish consumption. (C)

2007 Elsevier Selleck Blebbistatin B.V. All rights reserved.”
“The transcription factor p53 regulates cellular integrity in response to stress. p53 is mutated in more than half of cancerous

cells, with a majority of the mutations localized to the DNA binding domain (DBD). In order to map the structural and dynamical features of the DBD, we carried out multiple copy molecular dynamics simulations (totaling 0.8 mu s). Simulations show the loop 1 to be the most dynamic element among the DNA-contacting loops (loops 1-3). Loop 1 occupies two major conformational states: extended and recessed; the former but not the latter displays correlations in atomic fluctuations with those of loop 2 (similar to 24 angstrom GS 1101 apart). Since loop 1 binds to the major groove whereas loop 2 binds to the minor groove of DNA, our results begin to provide some insight into the possible mechanism underpinning the cooperative nature of DBD binding to DNA. We propose (1) a novel mechanism underlying the dynamics of loop 1 and the possible tread-milling of p53 on DNA and (2) possible mutations on loop 1 residues to restore the transcriptional activity of an oncogenic mutation at a distant site.”
“A new possibility for estimating the octanol/water coefficient (log P) was investigated using only one descriptor, the semi-empirical electrotopological

index (I(SET)). The predictability of four octanol/water partition coefficient (log P) calculation models was compared using a set of 131 aliphatic organic compounds from five different classes. Log P values were calculated employing 3-deazaneplanocin A Epigenetics inhibitor atomic-contribution methods, as in the Ghose/Crippen approach and its later refinement, AlogP; using fragmental methods through the ClogP method; and employing an approach considering the whole molecule using topological indices with the MlogP method. The efficiency and the applicability of the ISET in terms of calculating log P were demonstrated through good statistical quality (r > 0.99; s < 0.18), high internal stability and good predictive ability for an external group of compounds in the same order as the widely used models based on the fragmental method, ClogP, and the atomic contribution method, AlogP, which are among the most used methods of predicting log P.