The visual evoked field potential in the congenital acallosal mouse

The congenital absence of corpus callosum has been recently found to occur among some mice of the ddN strain in our laboratory. In this experiment, the differences of the visual evoked potentials among the normal corpus callosum, callosal hypogenesis and agenesis in ddN strain mice were investigated. One-Hz- flash stimulations were given on the left eye through a glass fiber connector from the EEG stimulator. Under Nembutal anesthesia, two hundred times of average evoked field potentials were recorded from the contralateral and ipsilateral visual cortices. Electrophysiologically, the normal mice showed complete decussation on the opic chiasm. On the other hand, the complete acallosal mice could be classified into two types, such as those of complete decussation and those of absence of optic chiasm. In the complete decussation of acallosal mice, the latency, peak latency and duration of these potentials from ipsilateral side significantly prolonged, and the amplitude of the potentials extremely diminished. In the absence of optic chiasm of complete acallosal mice, the potentials were obtained only in ipsilateral cortex. After amputation of the corpus callosum in the normal mice, the visual evoked field potential showed similar to acallosal mice. However, in the hypogenesis of corpus callosum, there was no significant difference in the potentials compared with the normal mice

Challenges and advances in computational docking: 2009 in review

Docking is a computational technique that places a small molecule (ligand) in the binding site of its macromolecular target (receptor) and estimates its binding affinity. This review addresses methodological developments that have occurred in the docking field in 2009, with a particular focus on the more difficult, and sometimes controversial, aspects of this promising computational discipline. These developments aim to address the main challenges of docking: receptor representation (such aspects as structural waters, side chain protonation, and, most of all, flexibility (from side chain rotation to domain movement)), ligand representation (protonation, tautomerism and stereoisomerism, and the effect of input conformation), as well as accounting for solvation and entropy of binding. This review is strongly focused on docking advances in the context of drug design, specifically in virtual screening and fragment-based drug design