[Another discussion of membrane voltage alterations in growing pollen tube].

Here we give a critical analysis of the opinion of Andreev (2011) on membrane potential distribution along the pollen tube plasmalemma. He assumes that a lateral gradient of dipole potential exists, but suggests a lateral gradient of transmembrane potential impossible. We demonstrate by concrete examples that the argumentation of the initiator of discussion is based on inaccurate citation of our experimental data (Breygina et al., 2009) and incomplete analysis of previously published articles. Speaking about transmembrane potential, he doesn't consider numerous facts demonstrating the uneven distribution of transmembrane ion fluxes and ion-transport proteins in the pollen tube plasmalemma, as well as data obtained by modeling of transmembrane potential distribution in objects of different shape. In addition, the assumption on the uneven distribution of dipole potential doesn't have an experimental basis neither in studies of the pollen tube, nor in the practice of using fluorescent voltage-sensitive dyes DiBAC4(3) and Di-4-ANEPPS. We are expecting the author to obtain experimental data in support of his position.

Simultaneous determination of methylated barbiturates and other anticonvulsant drugs by high-resolution gas chromatography.

Several barbiturates and other anticonvulsant drugs can be analyzed simultaneously as dimethylated derivatives by high-resolution gas chromatography with a solid flash methylation injector. Quantitative determinations were performed on test serum during a quality control scheme. The sensitivity (+/- 0.1 mug/ml) and the accuracy are compatible with the measurement of therapeutic levels of barbiturates. The advantages of the method are discussed.