Physiological adaptation of the diatom Pseudo-nitzschia delicatissima under copper starvation.

In the open ocean and particularly in iron (Fe)-limited environment, copper (Cu) deficiency might limit the growth of phytoplankton species. Cu is an essential trace metal used in electron-transfer reactions, such as respiration and photosynthesis, when bound to specific enzymes. Some phytoplankton species, such as the diatom Pseudo-nitzschia spp.

Link between domoic acid production and cell physiology after exchange of bacterial communities between toxic Pseudo-nitzschia multiseries and non-toxic Pseudo-nitzschia delicatissima.

Bacteria are known to influence domoic acid (DA) production by Pseudo-nitzschia spp., but the link between DA production and physiology of diatoms requires more investigation. We compared a toxic P.

Impact of copper exposure on Pseudo-nitzschia spp. physiology and domoic acid production.

Microalgae have differing sensitivities to copper toxicity. Some species within the genus Pseudo-nitzschia produce domoic acid (DA), a phycotoxin that has been hypothesised to chelate Cu and ameliorate Cu toxicity to the cells. To better characterise the effect of Cu on Pseudo-nitzschia, a toxic strain of P.

A new insight into allelopathic effects of Alexandrium minutum on photosynthesis and respiration of the diatom Chaetoceros neogracile revealed by photosynthetic-performance analysis and flow cytometry.

The allelopathic effects of Alexandrium minutum, a toxic dinoflagellate, on the diatom Chaetoceros neogracile were evaluated using unialgal cultures evaluated by flow cytometry (FCM) and photosynthetic-performance analysis. Using FCM, we demonstrated that red chlorophyll fluorescence, relative cell size (Forward scatter of blue laser light, FSC) and cell complexity (Side scatter, 90°-angle scatter of blue laser light, SSC) significantly and rapidly decreased in C. neogracile cells exposed to A.

Cell-based measurements to assess physiological status of Pseudo-nitzschia multiseries, a toxic diatom.

Diatoms of the genus Pseudo-nitzschia are potentially toxic microalgae, whose blooms can trigger amnesic shellfish poisoning. The purpose of this study was to test and adapt different probes and procedures in order to assess the physiological status of Pseudo-nitzschia multiseries at the cell level using flow cytometry. To perform these analyses, probes and procedures were first optimized for concentration and incubation time.

Effect on neurostimulation of injectates used for perineural space expansion before placement of a stimulating catheter: normal saline versus dextrose 5% in water.

Background And Objectives: We clinically assessed the electrophysiologic effect of dextrose 5% in water (D5W) and of normal saline (NS) used for expansion of the perineural space before placing a stimulating catheter. We questioned if higher current was required with NS but not with D5W, as has been observed experimentally.

Methods: This was a prospective randomized double-blind study of ASA I to II patients scheduled for total knee replacement.