(C) 2008 Elsevier Ltd. All rights reserved.”
“Oxaliplatin is a novel chemotherapeutic agent which is effective against advanced colorectal cancer, but at the same time causes severe neuropathy in the peripheral nerve fibres, affecting mainly the voltage-gated sodium (Na(+)) channels (VGNaCs), according find more to literature. In this study the effects of oxaliplatin on the peripheral myelinated nerve fibres (PMNFs) were investigated in vitro using the isolated sciatic nerve

of the adult rat. The advantage of this nerve-preparation was that stable in amplitude evoked compound action potentials (CAP) were recorded for over 1000 min. Incubation of the sciatic nerve fibres in 25, 100 and 500 mu M oxaliplatin, for 300-700 min caused dramatic distortion of the waveform of the CAP, namely broadening the repolarization phase, repetitive firing and afterhyperpolarization (AHP), related to the malfunction of voltage-gated Osimertinib cost potassium (K(+)) channels (VGKCs). At a concentration of 5 mu M, oxaliplatin caused broadening of the repolarization phase of the CAP only, while the no observed effect concentration

was estimated to be 1 mu M. These findings are indicative of severe effects of oxaliplatin on the VGKCs. In contrast, the amplitude and the rise-time of the depolarization of the CAP did not change significantly, a clear indication that the VGNaCs of the particular nerve preparation were not affected by oxaliplatin. The effects of from oxaliplatin on the PMNFs were similar to those of 4-aminopyridine (4-AP), a classical antagonist of VGKCs. These similarities in the pattern of action between oxaliplatin and 4-AP combined with the fact that the effects of oxaliplatin were more pronounced and developed at lower concentrations suggest that oxaliplatin acts

as a potent VGKCs antagonist. (c) 2008 Elsevier Inc. All rights reserved.”
“This paper considers the coevolution of phenotypic traits in a community comprising two competitive species subject to strong Allee effects. Firstly, we investigate the ecological and evolutionary conditions that allow for continuously stable strategy under symmetric competition. Secondly, we find that evolutionary suicide is impossible when the two species undergo symmetric competition, however, evolutionary suicide can occur in an asymmetric competition model with strong Allee effects. Thirdly, it is found that evolutionary bistability is a likely outcome of the process under both symmetric and asymmetric competitions, which depends on the properties of symmetric and asymmetric competitions. Fourthly, under asymmetric competition, we find that evolutionary cycle is a likely outcome of the process, which depends on the properties of both intraspecific and interspecific competition.